Quarterly report pursuant to Section 13 or 15(d)

CONSOLIDATED SCHEDULE OF INVESTMENTS

v3.22.2.2
CONSOLIDATED SCHEDULE OF INVESTMENTS
£ in Thousands
9 Months Ended 12 Months Ended
Sep. 30, 2022
USD ($)
shares
Dec. 31, 2021
USD ($)
shares
Sep. 30, 2022
GBP (£)
shares
Dec. 31, 2021
GBP (£)
shares
Sep. 30, 2021
USD ($)
Dec. 31, 2020
USD ($)
Investment Holdings [Line Items]            
Investment cost $ 2,869,469,000 $ 2,390,984,000        
Investments at Fair Value 2,825,738,000 2,434,522,000        
Equity            
Investment Holdings [Line Items]            
Investment cost 150,539,000 [1] 142,219,000 [2]        
Investments at Fair Value 134,134,000 184,710,000        
Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 31,148,000 [1] 27,147,000 [2]        
Investments at Fair Value 27,159,000 38,399,000        
Investments in Securities [Member]            
Investment Holdings [Line Items]            
Investment cost [2]   2,388,952,000        
Investments at Fair Value   2,432,708,000        
Investment [Member]            
Investment Holdings [Line Items]            
Investment cost [2]   2,390,984,000        
Investments at Fair Value   2,434,522,000        
Investment Funds & Vehicles [Member]            
Investment Holdings [Line Items]            
Investment cost [1] 3,139,000          
Investments at Fair Value 3,046,000          
Senior Secured            
Investment Holdings [Line Items]            
Investments at Fair Value 2,607,006,000 $ 2,156,709,000        
Senior Secured | Blue Sprig Pediatrics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment, Interest Rate, Paid in Kind   4.45%   4.45%    
Total Investments Before Cash And Cash Equivalent [Member]            
Investment Holdings [Line Items]            
Investment cost [1],[3] 2,869,469,000          
Investments at Fair Value 2,825,738,000          
Total Investments with Cash and Cash Equivalents            
Investment Holdings [Line Items]            
Investment cost [1],[3] 2,894,469,000          
Investments at Fair Value [3] 2,850,738,000          
Total investments In Securities            
Investment Holdings [Line Items]            
Investment cost [1] 2,866,330,000          
Investments at Fair Value 2,822,692,000          
Cash and Cash Equivalents | G S Financial Square Government Fund            
Investment Holdings [Line Items]            
Investment cost [1] 25,000,000          
Investments at Fair Value 25,000,000          
Money Market Funds [Member]            
Investment Holdings [Line Items]            
Investment cost [1],[3] 25,000,000          
Investments at Fair Value [3] 25,000,000          
Debt Investments            
Investment Holdings [Line Items]            
Investment cost 2,684,643,000 [1] $ 2,219,586,000 [2]        
Investments at Fair Value 2,661,399,000 2,209,599,000        
Unsecured            
Investment Holdings [Line Items]            
Investments at Fair Value 54,393,000 52,890,000        
Communications & Networking            
Investment Holdings [Line Items]            
Investments at Fair Value 101,094,000 105,490,000        
Communications & Networking | Equity            
Investment Holdings [Line Items]            
Investment cost [2]   1,230,000        
Investments at Fair Value   6,260,000        
Communications & Networking | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 541,000 [1] 418,000 [2]        
Investments at Fair Value 140,000 0        
Communications & Networking | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 98,596,000 [1] 97,088,000 [4]        
Investments at Fair Value 100,954,000 99,230,000        
Communications & Networking | Aryaka Networks, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] 123,000          
Investments at Fair Value $ 140,000          
Investment, Acquisition Date [5] Jun. 28, 2022          
Shares | shares 229,611   229,611      
Communications & Networking | Peerless Network Holdings, Inc. | Equity            
Investment Holdings [Line Items]            
Investment cost [2]   1,230,000        
Investments at Fair Value   $ 6,260,000        
Shares | shares   1,138,328   1,138,328    
Communications & Networking | Peerless Network Holdings, Inc. | Equity | Preferred Series A            
Investment Holdings [Line Items]            
Investment cost [2]   $ 1,230,000        
Investments at Fair Value   $ 6,242,000        
Investment, Acquisition Date [6]   Apr. 11, 2008        
Shares | shares   1,135,000   1,135,000    
Communications & Networking | Peerless Network Holdings, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2]   $ 0        
Investments at Fair Value   $ 18,000        
Investment, Acquisition Date [6]   Oct. 21, 2020        
Shares | shares   3,328   3,328    
Communications & Networking | Spring Mobile Solutions, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 418,000 [1] $ 418,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Apr. 19, 2013 [5] Apr. 19, 2013 [6]        
Shares | shares 2,834,375 2,834,375 2,834,375 2,834,375    
Communications & Networking | Senior Secured | Aryaka Networks, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-07   2026-07      
Investment, Basis Spread, Variable Rate [7] 3.25%   3.25%      
Investment, Interest Rate, Floor [7] 6.75%   6.75%      
Investment, Interest Rate, Paid in Kind [7] 1.05%   1.05%      
Principal Amount [8],[9],[10] $ 5,009,000          
Investment cost [1],[8],[9],[10] 4,943,000          
Investments at Fair Value [8],[9],[10] $ 4,943,000          
Communications & Networking | Senior Secured | Cytracom Holdings LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-02 2025-02 2025-02 2025-02    
Investment, Basis Spread, Variable Rate 9.31% [7] 9.31% [11] 9.31% [7] 9.31% [11]    
Investment, Interest Rate, Floor 10.31% [7] 10.31% [11] 10.31% [7] 10.31% [11]    
Principal Amount $ 8,933,000 [10],[12],[13] $ 9,000,000 [14],[15],[16]        
Investment cost 8,776,000 [1],[10],[12],[13] 8,802,000 [4],[14],[15],[16]        
Investments at Fair Value $ 8,728,000 [10],[12],[13] $ 8,725,000 [14],[15],[16]        
Communications & Networking | Senior Secured | Rocket Lab Global Services, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-06 2024-06 2024-06 2024-06    
Investment Interest Rate [11]   3.25%   3.25%    
Investment, Basis Spread, Variable Rate 4.90% [7] 4.90% [11] 4.90% [7] 4.90% [11]    
Investment, Interest Rate, Floor 8.15% [7] 8.15% [11] 8.15% [7] 8.15% [11]    
Investment, Interest Rate, Paid in Kind 1.25% [7] 1.25% [11] 1.25% [7] 1.25% [11]    
Interest Rate and Floor [11]   3.25%   3.25%    
Principal Amount $ 84,314,000 [9],[12],[17],[18],[19] $ 88,542,000 [20],[21]        
Investment cost 84,877,000 [1],[9],[12],[17],[18],[19] 88,286,000 [4],[20],[21]        
Investments at Fair Value $ 87,283,000 [9],[12],[17],[18],[19] 90,505,000 [20],[21]        
Communications & Networking | Senior Secured | Exit Fee | Aryaka Networks, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.55%   3.55%      
Interest Rate and Floor [7] 3.55%   3.55%      
Communications & Networking | Senior Secured | Exit Fee | Rocket Lab Global Services, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.20%   3.20%      
Interest Rate and Floor [7] 3.20%   3.20%      
Communications & Networking | Debt Investments            
Investment Holdings [Line Items]            
Investment cost $ 98,596,000 [1] 97,088,000 [4]        
Investments at Fair Value 100,954,000 99,230,000        
Consumer & Business Products            
Investment Holdings [Line Items]            
Investments at Fair Value 25,497,000 28,099,000        
Consumer & Business Products | Equity            
Investment Holdings [Line Items]            
Investment cost 561,000 [1] 128,000 [2]        
Investments at Fair Value 185,000 447,000        
Consumer & Business Products | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 1,712,000 [1] 2,145,000 [2]        
Investments at Fair Value 1,122,000 4,354,000        
Consumer & Business Products | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Principal Amount [4]   23,162,000        
Investment cost [1] 23,774,000          
Investments at Fair Value 24,190,000 23,298,000        
Consumer & Business Products | Grove Collaborative, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5],[22] 433,000          
Investments at Fair Value [5],[22] $ 127,000          
Investment, Acquisition Date [5] Apr. 30, 2021          
Shares | shares [5],[22] 61,300   61,300      
Consumer & Business Products | Grove Collaborative, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2]   433,000        
Investments at Fair Value   $ 326,000        
Investment, Acquisition Date [6]   Apr. 30, 2021        
Shares | shares   83,625   83,625    
Consumer & Business Products | Penumbra Brands, LLC (p.k.a. Gadget Guard) | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2]   $ 228,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Jun. 03, 2014        
Shares | shares   1,662,441   1,662,441    
Consumer & Business Products | TechStyle, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 128,000 [1] $ 128,000 [2]        
Investments at Fair Value $ 58,000 $ 447,000        
Investment, Acquisition Date Apr. 30, 2010 [5] Apr. 30, 2010 [6]        
Shares | shares 42,989 42,989 42,989 42,989    
Consumer & Business Products | TechStyle, Inc. | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost [1] $ 1,101,000          
Investments at Fair Value $ 365,000          
Investment, Acquisition Date [5] Jul. 16, 2013          
Shares | shares 206,185   206,185      
Consumer & Business Products | Gadget Guard, LLC | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 228,000          
Investments at Fair Value $ 0          
Investment, Acquisition Date [5] Jun. 03, 2014          
Shares | shares 1,662,441   1,662,441      
Consumer & Business Products | The Neat Company | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 365,000 [1] $ 365,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Aug. 13, 2014 [5] Aug. 13, 2014 [6]        
Shares | shares 54,054 54,054 54,054 54,054    
Consumer & Business Products | Whoop, Inc. | Warrant Investment | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 18,000 [1] $ 18,000 [2]        
Investments at Fair Value $ 757,000 $ 1,847,000        
Investment, Acquisition Date Jun. 27, 2018 [5] Jun. 27, 2018 [6]        
Shares | shares 686,270 686,270 686,270 686,270    
Consumer & Business Products | TechStyle, Inc. (p.k.a. Just Fabulous, Inc.) | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost [2]   $ 1,101,000        
Investments at Fair Value   $ 2,181,000        
Investment, Acquisition Date [6]   Jul. 16, 2013        
Shares | shares   206,185   206,185    
Consumer & Business Products | Senior Secured | Grove Collaborative, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-04 2025-04 2025-04 2025-04    
Investment Interest Rate [11]   6.75%   6.75%    
Investment, Basis Spread, Variable Rate 5.50% [7] 5.50% [11] 5.50% [7] 5.50% [11]    
Investment, Interest Rate, Floor 8.75% [7] 8.75% [11] 8.75% [7] 8.75% [11]    
Interest Rate and Floor [11]   6.75%   6.75%    
Principal Amount $ 23,520,000 [8] $ 23,520,000 [23]        
Investment cost 23,774,000 [1],[8] 23,162,000 [4],[23]        
Investments at Fair Value $ 24,190,000 [8] 23,298,000 [23]        
Consumer & Business Products | Senior Secured | Exit Fee | Grove Collaborative, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 8.75%   8.75%      
Interest Rate and Floor [7] 8.75%   8.75%      
Consumer & Business Products | Debt Investments            
Investment Holdings [Line Items]            
Principal Amount [4]   23,162,000        
Investment cost [1] $ 23,774,000          
Investments at Fair Value 24,190,000 23,298,000        
Diversified Financial Services            
Investment Holdings [Line Items]            
Investments at Fair Value 72,061,000 65,073,000        
Diversified Financial Services | Equity            
Investment Holdings [Line Items]            
Investment cost 28,444,000 [1] 28,041,000 [2]        
Investments at Fair Value 38,022,000 32,608,000        
Diversified Financial Services | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment cost [4]   403,000        
Investments at Fair Value   403,000        
Diversified Financial Services | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 36,545,000 [1] 33,335,000 [4]        
Investments at Fair Value 34,039,000 32,062,000        
Diversified Financial Services | Gibraltar Business Capital, LLC | Equity            
Investment Holdings [Line Items]            
Investment cost 28,006,000 [1] 28,006,000 [2]        
Investments at Fair Value $ 15,623,000 $ 20,618,000        
Shares | shares 11,432,752 11,432,752 11,432,752 11,432,752    
Diversified Financial Services | Gibraltar Business Capital, LLC | Equity | Preferred Series A            
Investment Holdings [Line Items]            
Investment cost $ 26,122,000 [1],[24] $ 26,122,000 [2],[25]        
Investments at Fair Value $ 14,489,000 [24] $ 19,393,000 [25]        
Investment, Acquisition Date Mar. 01, 2018 [5] Mar. 01, 2018 [6],[25]        
Shares | shares 10,602,752 [24] 10,602,752 [25] 10,602,752 [24] 10,602,752 [25]    
Diversified Financial Services | Gibraltar Business Capital, LLC | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,884,000 [1],[24] $ 1,884,000 [2],[25]        
Investments at Fair Value $ 1,134,000 [24] $ 1,225,000 [25]        
Investment, Acquisition Date Mar. 01, 2018 [5] Mar. 01, 2018 [6],[25]        
Shares | shares 830,000 [24] 830,000 [25] 830,000 [24] 830,000 [25]    
Diversified Financial Services | Gibraltar Business Capital, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Principal Amount $ 25,000,000 $ 25,000,000        
Investment cost 24,545,000 [1] 24,485,000 [4]        
Investments at Fair Value 22,039,000 23,212,000        
Diversified Financial Services | Hercules Adviser LLC | Equity | Member Units            
Investment Holdings [Line Items]            
Investment cost 35,000 [1],[24] 35,000 [2],[25]        
Investments at Fair Value $ 21,945,000 [24] $ 11,990,000 [25]        
Investment, Acquisition Date Mar. 26, 2021 [5] Mar. 26, 2021 [6],[25]        
Shares | shares 1 [24] 1 [25] 1 [24] 1 [25]    
Diversified Financial Services | Newfront Insurance Holdings, Inc. | Equity | Preferred Series D-2            
Investment Holdings [Line Items]            
Investment cost [1] $ 403,000          
Investments at Fair Value $ 454,000          
Investment, Acquisition Date [5] Sep. 30, 2021          
Shares | shares 210,282   210,282      
Diversified Financial Services | Debt Investments            
Investment Holdings [Line Items]            
Investment cost $ 36,545,000 [1] $ 33,738,000 [4]        
Investments at Fair Value $ 34,039,000 $ 32,465,000        
Diversified Financial Services | Unsecured | Gibraltar Business Capital, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2026-09   2026-09    
Principal Amount [25]   $ 15,000,000        
Diversified Financial Services | Unsecured | Hercules Adviser LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-06   2025-06      
Investment, Interest Rate, Paid in Cash [7] 5.00%   5.00%      
Principal Amount [24] $ 12,000,000          
Investment cost [1],[24] 12,000,000          
Investments at Fair Value [24] $ 12,000,000          
Diversified Financial Services | Unsecured 14.50% | Gibraltar Business Capital, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-09   2026-09      
Investment, Interest Rate, Paid in Cash 14.50% [7] 14.50% [11],[25] 14.50% [7] 14.50% [11],[25]    
Principal Amount [24] $ 15,000,000          
Investment cost 14,701,000 [1],[24] $ 14,662,000 [4],[25]        
Investments at Fair Value $ 13,033,000 [24] $ 13,818,000 [25]        
Diversified Financial Services | Unsecured 11.50% | Gibraltar Business Capital, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-09 2026-09 2026-09 2026-09    
Investment, Interest Rate, Paid in Cash 11.50% [7] 11.50% [11],[25] 11.50% [7] 11.50% [11],[25]    
Principal Amount $ 10,000,000 [24] $ 10,000,000 [25]        
Investment cost 9,844,000 [1],[24] 9,823,000 [4],[25]        
Investments at Fair Value 9,006,000 [24] $ 9,394,000 [25]        
Diversified Financial Services | Unsecured 5.00 % | Hercules Adviser LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2023-05   2023-05    
Investment, Interest Rate, Paid in Cash [11],[25]   5.00%   5.00%    
Principal Amount [25]   $ 8,850,000        
Investment cost [4],[25]   8,850,000        
Investments at Fair Value [25]   $ 8,850,000        
Diversified Financial Services | Convertible Debt | Newfront Insurance Holdings, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date   2022-08   2022-08    
Investment, Interest Rate, Floor [11],[26]   0.19%   0.19%    
Investment, Interest Rate, Paid in Kind [11],[26]   0.19%   0.19%    
Principal Amount [26]   $ 403,000        
Investment cost [4],[26]   403,000        
Investments at Fair Value [26]   403,000        
Investment Funds And Vehicles            
Investment Holdings [Line Items]            
Investment cost [2]   2,032,000        
Investments at Fair Value   1,814,000        
Investment Funds And Vehicles | Forbion Growth Opportunities Fund I C V            
Investment Holdings [Line Items]            
Investment cost [2],[15],[27],[28]   2,032,000        
Investments at Fair Value [15],[27],[28]   $ 1,814,000        
Investment, Acquisition Date [6],[27],[28]   Nov. 16, 2020        
Surgical Devices            
Investment Holdings [Line Items]            
Investments at Fair Value 1,536,000 $ 1,029,000        
Surgical Devices | Equity            
Investment Holdings [Line Items]            
Investment cost 1,941,000 [1] 1,941,000 [2]        
Investments at Fair Value 0 543,000        
Surgical Devices | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 152,000 [1] 206,000 [2]        
Investments at Fair Value 1,536,000 486,000        
Surgical Devices | Gynesonics, Inc. | Equity            
Investment Holdings [Line Items]            
Investment cost 1,941,000 [1] 1,941,000 [2]        
Investments at Fair Value $ 0 $ 543,000        
Shares | shares 9,595,178 9,595,178 9,595,178 9,595,178    
Surgical Devices | Gynesonics, Inc. | Equity | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost $ 712,000 [1] $ 712,000 [2]        
Investments at Fair Value $ 0 $ 81,000        
Investment, Acquisition Date Feb. 08, 2013 [5] Feb. 08, 2013 [6]        
Shares | shares 1,991,157 1,991,157 1,991,157 1,991,157    
Surgical Devices | Gynesonics, Inc. | Equity | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost $ 250,000 [1] $ 250,000 [2]        
Investments at Fair Value $ 0 $ 9,000        
Investment, Acquisition Date Jan. 18, 2007 [5] Jan. 18, 2007 [6]        
Shares | shares 219,298 219,298 219,298 219,298    
Surgical Devices | Gynesonics, Inc. | Equity | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 282,000 [1] $ 282,000 [2]        
Investments at Fair Value $ 0 $ 26,000        
Investment, Acquisition Date Jun. 16, 2010 [5] Jun. 16, 2010 [6]        
Shares | shares 656,538 656,538 656,538 656,538    
Surgical Devices | Gynesonics, Inc. | Equity | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost $ 429,000 [1] $ 429,000 [2]        
Investments at Fair Value $ 0 $ 131,000        
Investment, Acquisition Date Jul. 14, 2015 [5] Jul. 14, 2015 [6]        
Shares | shares 2,786,367 2,786,367 2,786,367 2,786,367    
Surgical Devices | Gynesonics, Inc. | Equity | Preferred Series F            
Investment Holdings [Line Items]            
Investment cost $ 118,000 [1] $ 118,000 [2]        
Investments at Fair Value $ 0 $ 123,000        
Investment, Acquisition Date Dec. 18, 2018 [5] Dec. 18, 2018 [6]        
Shares | shares 1,523,693 1,523,693 1,523,693 1,523,693    
Surgical Devices | Gynesonics, Inc. | Equity | Series F One Preferred Stock            
Investment Holdings [Line Items]            
Investment cost $ 150,000 [1] $ 150,000 [2]        
Investments at Fair Value $ 0 $ 173,000        
Investment, Acquisition Date Dec. 18, 2018 [5] Dec. 18, 2018 [6]        
Shares | shares 2,418,125 2,418,125 2,418,125 2,418,125    
Surgical Devices | Gynesonics, Inc. | Warrant Investment | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 13,000 [1] $ 67,000 [2]        
Investments at Fair Value $ 0 $ 6,000        
Investment, Acquisition Date Dec. 05, 2012 [5] Feb. 08, 2012 [6]        
Shares | shares 33,670 151,123 33,670 151,123    
Surgical Devices | TransMedics Group, Inc. (p.k.a Transmedics, Inc.) | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 139,000 [1],[5] $ 139,000 [2],[6]        
Investments at Fair Value $ 1,536,000 [5] $ 480,000 [6]        
Investment, Acquisition Date Nov. 07, 2012 [5] Nov. 07, 2012        
Shares | shares 64,440 [5] 64,440 [6] 64,440 [5] 64,440 [6]    
Drug Discovery & Development            
Investment Holdings [Line Items]            
Investments at Fair Value $ 1,091,827,000 $ 967,383,000        
Drug Discovery & Development | Equity            
Investment Holdings [Line Items]            
Investment cost 42,548,000 [1] 33,401,000 [2]        
Investments at Fair Value 32,844,000 24,860,000        
Drug Discovery & Development | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 7,709,000 [1] 7,393,000 [2]        
Investments at Fair Value 4,074,000 4,745,000        
Drug Discovery & Development | Investment Funds & Vehicles [Member]            
Investment Holdings [Line Items]            
Investment cost [1] 2,758,000          
Investments at Fair Value 2,665,000          
Drug Discovery & Development | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment cost 16,378,000 [1] 20,036,000 [4]        
Investments at Fair Value 16,093,000 20,036,000        
Drug Discovery & Development | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 1,039,957,000 [1] 916,421,000 [2]        
Investments at Fair Value 1,036,151,000 915,928,000        
Drug Discovery & Development | Chemocentryx, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost 1,000,000 [1],[5],[29] 1,000,000 [2],[6],[27]        
Investments at Fair Value $ 891,000 [5],[29] $ 628,000 [6],[27]        
Investment, Acquisition Date Jun. 15, 2020 [5] Jun. 15, 2020 [6],[27]        
Shares | shares 17,241 [5],[29] 17,241 [6],[27] 17,241 [5],[29] 17,241 [6],[27]    
Drug Discovery & Development | Akero Therapeutics, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 1,000,000          
Investments at Fair Value [5],[29] $ 1,310,000          
Investment, Acquisition Date [5] Sep. 19, 2022          
Shares | shares [5],[29] 38,461   38,461      
Drug Discovery & Development | Akero Therapeutics, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5],[29] $ 56,000          
Investments at Fair Value [5],[29] $ 398,000          
Investment, Acquisition Date [5] Jun. 15, 2022          
Shares | shares [5],[29] 18,360   18,360      
Drug Discovery & Development | Albireo Pharma, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,000,000 [1],[5],[29] $ 1,000,000 [2],[6],[27]        
Investments at Fair Value $ 484,000 [5],[29] $ 582,000 [6],[27]        
Investment, Acquisition Date Sep. 14, 2020 [5] Sep. 14, 2020 [6],[27]        
Shares | shares 25,000 [5],[29] 25,000 [6],[27] 25,000 [5],[29] 25,000 [6],[27]    
Drug Discovery & Development | Albireo Pharma, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 61,000 [1],[5],[29] $ 61,000 [2],[6],[27]        
Investments at Fair Value $ 26,000 [5],[29] $ 42,000 [6],[27]        
Investment, Acquisition Date Jun. 08, 2020 [5] Jun. 08, 2020 [6],[27]        
Shares | shares 5,311 [5],[29] 5,311 [6],[27] 5,311 [5],[29] 5,311 [6],[27]    
Drug Discovery & Development | Aveo Pharmaceuticals, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,715,000 [1],[5] $ 1,715,000 [2],[6]        
Investments at Fair Value $ 1,565,000 [5] $ 892,000 [6]        
Investment, Acquisition Date Jul. 31, 2011 [5] Jul. 31, 2011 [6]        
Shares | shares 190,179 [5] 190,179 [6] 190,179 [5] 190,179 [6]    
Drug Discovery & Development | Axsome Therapeutics, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5],[19],[22],[29] $ 4,165,000          
Investments at Fair Value [5],[19],[22],[29] $ 5,360,000          
Investment, Acquisition Date [5] May 09, 2022          
Shares | shares [5],[19],[22],[29] 127,021   127,021      
Drug Discovery & Development | Axsome Therapeutics, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 880,000 [1],[5],[19],[29] $ 681,000 [2],[6],[27]        
Investments at Fair Value $ 783,000 [5],[19],[29] $ 142,000 [6],[27]        
Investment, Acquisition Date Sep. 25, 2020 [5] Sep. 25, 2020 [6],[27]        
Shares | shares 40,396 [5],[19],[22],[29] 15,541 [6],[27] 40,396 [5],[19],[22],[29] 15,541 [6],[27]    
Drug Discovery & Development | Bicycle Therapeutics PLC | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,871,000 [1],[5],[29],[30] $ 1,871,000 [2],[6],[27],[28]        
Investments at Fair Value $ 2,282,000 [5],[29],[30] $ 5,971,000 [6],[27],[28]        
Investment, Acquisition Date Oct. 05, 2020 [5] Oct. 05, 2020 [6],[27],[28]        
Shares | shares 98,100 [5],[29],[30] 98,100 [6],[27],[28] 98,100 [5],[29],[30] 98,100 [6],[27],[28]    
Drug Discovery & Development | BridgeBio Pharma, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 2,255,000 [1],[5] $ 2,255,000 [2],[6]        
Investments at Fair Value $ 2,299,000 [5] $ 3,859,000 [6]        
Investment, Acquisition Date Jun. 21, 2018 [5] Jun. 21, 2018 [6]        
Shares | shares 231,329 [5] 231,329 [6] 231,329 [5] 231,329 [6]    
Drug Discovery & Development | Cellarity, Inc. | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost $ 287,000 [1],[31] $ 287,000 [2],[32]        
Investments at Fair Value $ 370,000 [31] $ 287,000 [32]        
Investment, Acquisition Date Dec. 08, 2021 [5] Dec. 08, 2021 [6]        
Shares | shares 100,000 [31] 100,000 [32] 100,000 [31] 100,000 [32]    
Drug Discovery & Development | Century Therapeutics, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 37,000 [1],[5] $ 37,000 [2],[6]        
Investments at Fair Value $ 16,000 [5] $ 64,000 [6]        
Investment, Acquisition Date Sep. 14, 2020 [5] Sep. 14, 2020 [6]        
Shares | shares 16,112 [5] 16,112 [6] 16,112 [5] 16,112 [6]    
Drug Discovery & Development | enGene, Inc. | Warrant Investment | Preferred Series 3            
Investment Holdings [Line Items]            
Investment cost [1],[29],[30] $ 72,000          
Investments at Fair Value [29],[30] $ 31,000          
Investment, Acquisition Date [5] Dec. 30, 2021          
Shares | shares [29],[30] 133,692   133,692      
Drug Discovery & Development | enGene, Inc. | Warrant Investment | Preferred Series 3 Class C            
Investment Holdings [Line Items]            
Investment cost [2],[27],[28]   $ 64,000        
Investments at Fair Value [27],[28]   $ 64,000        
Investment, Acquisition Date [6],[27],[28]   Dec. 30, 2021        
Shares | shares [27],[28]   84,714   84,714    
Drug Discovery & Development | Hibercell, Inc. | Equity | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost $ 4,250,000 [1],[31] $ 4,250,000 [2],[32]        
Investments at Fair Value $ 2,917,000 [31] $ 3,264,000 [32]        
Investment, Acquisition Date May 07, 2021 [5] May 07, 2021 [6]        
Shares | shares 3,466,840 [31] 3,466,840 [32] 3,466,840 [31] 3,466,840 [32]    
Drug Discovery & Development | HilleVax, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5] $ 4,000,000          
Investments at Fair Value [5] $ 4,021,000          
Investment, Acquisition Date [5] May 03, 2022          
Shares | shares [5] 235,295   235,295      
Drug Discovery & Development | Humanigen, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 800,000 [1],[5],[29] $ 800,000 [2],[6],[27]        
Investments at Fair Value $ 8,000 [5],[29] $ 161,000 [6],[27]        
Investment, Acquisition Date Mar. 31, 2021 [5] Mar. 31, 2021 [6],[27]        
Shares | shares 43,243 [5],[29] 43,243 [6],[27] 43,243 [5],[29] 43,243 [6],[27]    
Drug Discovery & Development | Kaleido Biosciences, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2],[6]   $ 1,000,000        
Investments at Fair Value [6]   $ 207,000        
Investment, Acquisition Date [6]   Feb. 10, 2021        
Shares | shares [6]   86,585   86,585    
Drug Discovery & Development | Madrigal Pharmaceutical, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5],[29] $ 177,000          
Investments at Fair Value [5],[29] $ 214,000          
Investment, Acquisition Date [5] May 09, 2022          
Shares | shares [5],[29] 10,131   10,131      
Drug Discovery & Development | Phathom Pharmaceuticals, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 848,000 [1],[5],[19],[29],[31] $ 848,000 [2],[6],[27],[32]        
Investments at Fair Value $ 113,000 [5],[19],[29],[31] $ 307,000 [6],[21],[27],[32]        
Investment, Acquisition Date Sep. 17, 2021 [5] Sep. 17, 2021 [6],[27]        
Shares | shares 64,687 [5],[19],[29],[31] 64,687 [6],[21],[27],[32] 64,687 [5],[19],[29],[31] 64,687 [6],[21],[27],[32]    
Drug Discovery & Development | Provention Bio, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5] $ 281,000          
Investments at Fair Value [5] $ 224,000          
Investment, Acquisition Date [5] Sep. 15, 2022          
Shares | shares [5] 111,934   111,934      
Drug Discovery & Development | Redshift Bioanalytics, Inc. | Warrant Investment            
Investment Holdings [Line Items]            
Investments at Fair Value [31] $ 18,000          
Drug Discovery & Development | Redshift Bioanalytics, Inc. | Warrant Investment | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost [1],[31] $ 20,000          
Investment, Acquisition Date [5] Mar. 23, 2022          
Shares | shares [31] 475,510   475,510      
Drug Discovery & Development | Scynexis, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 296,000 [1],[5] $ 188,000 [2],[6]        
Investments at Fair Value $ 47,000 [5] $ 142,000 [6]        
Investment, Acquisition Date May 14, 2021 [5] May 14, 2021 [6]        
Shares | shares 106,035 [5] 90,887 [6] 106,035 [5] 90,887 [6]    
Drug Discovery & Development | Tarsus Pharmaceuticals, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5],[29] $ 2,100,000          
Investments at Fair Value [5],[29] $ 2,663,000          
Investment, Acquisition Date [5] May 05, 2022          
Shares | shares [5],[29] 155,555   155,555      
Drug Discovery & Development | TG Therapeutics, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,033,000 [1],[5],[18],[29] $ 1,033,000 [2],[6],[27],[33]        
Investments at Fair Value $ 335,000 [5],[18],[29] $ 2,172,000 [6],[27],[33]        
Investment, Acquisition Date Feb. 28, 2019 [5] Feb. 28, 2019 [6],[27]        
Shares | shares 231,613 [5],[18],[29] 231,613 [6],[27],[33] 231,613 [5],[18],[29] 231,613 [6],[27],[33]    
Drug Discovery & Development | Uni Qure B V | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 332,000 [1],[5],[19],[29],[30] $ 332,000 [2],[6],[21],[27],[28]        
Investments at Fair Value $ 322,000 [5],[19],[29],[30] $ 356,000 [6],[21],[27],[28]        
Investment, Acquisition Date Jan. 31, 2019 [5] Jan. 31, 2019 [6],[27],[28]        
Shares | shares 17,175 [5],[19],[29],[30] 17,175 [6],[21],[27],[28] 17,175 [5],[19],[29],[30] 17,175 [6],[21],[27],[28]    
Drug Discovery & Development | Valo Health L L C | Equity | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost $ 3,000,000 [1] $ 3,000,000 [2]        
Investments at Fair Value $ 3,622,000 $ 4,650,000        
Investment, Acquisition Date Dec. 11, 2020 [5] Dec. 11, 2020 [6]        
Shares | shares 510,308 510,308 510,308 510,308    
Drug Discovery & Development | Valo Health L L C | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investments at Fair Value $ 242,000          
Investment, Acquisition Date [5] Jun. 15, 2020          
Drug Discovery & Development | Valo Health L L C | Warrant Investment | Common Units            
Investment Holdings [Line Items]            
Investment cost [1] $ 256,000          
Shares | shares 102,216   102,216      
Drug Discovery & Development | X Four Pharmaceuticals Inc | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 2,522,000 [1],[5] $ 1,641,000 [2],[6]        
Investments at Fair Value $ 1,901,000 [5] $ 454,000 [6]        
Investment, Acquisition Date Nov. 26, 2019 [5] Nov. 26, 2019 [6]        
Shares | shares 1,111,519 [5] 198,277 [6] 1,111,519 [5] 198,277 [6]    
Drug Discovery & Development | X Four Pharmaceuticals Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 792,000 [1],[5] $ 673,000 [2],[6]        
Investments at Fair Value $ 628,000 [5] $ 2,000 [6]        
Investment, Acquisition Date Mar. 18, 2019 [5] Mar. 18, 2019 [6]        
Shares | shares 1,021,576 [5] 108,334 [6] 1,021,576 [5] 108,334 [6]    
Drug Discovery & Development | Applied Molecular Transport | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 42,000 [1],[5],[29] $ 42,000 [2],[6],[27]        
Investments at Fair Value $ 1,000 [5],[29] $ 14,000 [6],[27]        
Investment, Acquisition Date Apr. 06, 2021 [5] Apr. 06, 2021 [6],[27]        
Shares | shares 1,000 [5],[29] 1,000 [6],[27] 1,000 [5],[29] 1,000 [6],[27]    
Drug Discovery & Development | Avalo Therapeutics, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,000,000 [1],[5] $ 1,000,000 [2],[6]        
Investments at Fair Value $ 33,000 [5] $ 202,000 [6]        
Investment, Acquisition Date Aug. 19, 2014 [5] Aug. 19, 2014 [6]        
Shares | shares 9,924 [5] 119,087 [6] 9,924 [5] 119,087 [6]    
Drug Discovery & Development | Concert Pharmaceuticals, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,367,000 [1],[5],[29] $ 1,367,000 [2],[6],[27]        
Investments at Fair Value $ 474,000 [5],[29] $ 223,000 [6],[27]        
Investment, Acquisition Date Feb. 13, 2019 [5] Feb. 13, 2019 [6],[27]        
Shares | shares 70,796 [5],[29] 70,796 [6],[27] 70,796 [5],[29] 70,796 [6],[27]    
Drug Discovery & Development | Concert Pharmaceuticals, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2],[6],[27]   $ 178,000        
Investments at Fair Value [6],[27]   $ 3,000        
Investment, Acquisition Date [6],[27]   Jun. 08, 2017        
Shares | shares [6],[27]   61,273   61,273    
Drug Discovery & Development | Dare Biosciences, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,000,000 [1],[5] $ 1,000,000 [2],[6]        
Investments at Fair Value $ 14,000 [5] $ 27,000 [6]        
Investment, Acquisition Date Jan. 08, 2015 [5] Jan. 08, 2015 [6]        
Shares | shares 13,550 [5] 13,550 [6] 13,550 [5] 13,550 [6]    
Drug Discovery & Development | Dynavax Technologies | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 550,000 [1],[5],[29] $ 550,000 [2],[6],[27]        
Investments at Fair Value $ 209,000 [5],[29] $ 281,000 [6],[27]        
Investment, Acquisition Date Jul. 22, 2015 [5] Jul. 22, 2015 [6],[27]        
Shares | shares 20,000 [5],[29] 20,000 [6],[27] 20,000 [5],[29] 20,000 [6],[27]    
Drug Discovery & Development | NorthSea Therapeutics | Equity | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 2,000,000 [1],[29],[30] $ 2,000,000 [2],[27],[28]        
Investments at Fair Value $ 1,515,000 [29],[30] $ 2,000,000 [27],[28]        
Investment, Acquisition Date Dec. 15, 2021 [5] Dec. 15, 2021 [6],[27],[28]        
Shares | shares 983 [29],[30] 983 [27],[28] 983 [29],[30] 983 [27],[28]    
Drug Discovery & Development | Paratek Pharmaceuticals, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 2,744,000 [1],[5] $ 2,744,000 [2],[6]        
Investments at Fair Value $ 196,000 [5] $ 343,000 [6]        
Investment, Acquisition Date Feb. 26, 2007 [5] Feb. 26, 2007 [6]        
Shares | shares 76,362 [5] 76,362 [6] 76,362 [5] 76,362 [6]    
Drug Discovery & Development | Paratek Pharmaceuticals, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 520,000 [1],[5] $ 546,000 [2],[6]        
Investments at Fair Value $ 72,000 [5] $ 427,000 [6]        
Investment, Acquisition Date Aug. 01, 2018 [5] Jun. 27, 2017 [6]        
Shares | shares 426,866 [5] 432,240 [6] 426,866 [5] 432,240 [6]    
Drug Discovery & Development | Rocket Pharmaceuticals, Ltd. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,500,000 [1],[5] $ 1,500,000 [2],[6]        
Investments at Fair Value $ 15,000 [5] $ 21,000 [6]        
Investment, Acquisition Date Aug. 22, 2007 [5] Aug. 22, 2007 [6]        
Shares | shares 944 [5] 944 [6] 944 [5] 944 [6]    
Drug Discovery & Development | Savara, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 203,000 [1],[5] $ 202,000 [2],[6]        
Investments at Fair Value $ 17,000 [5] $ 14,000 [6]        
Investment, Acquisition Date Aug. 11, 2015 [5] Aug. 11, 2015 [6]        
Shares | shares 11,119 [5] 11,119 [6] 11,119 [5] 11,119 [6]    
Drug Discovery & Development | Sio Gene Therapies, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,269,000 [1],[5] $ 1,269,000 [2],[6],[27]        
Investments at Fair Value $ 4,000 [5] $ 21,000 [6],[27]        
Investment, Acquisition Date Feb. 02, 2017 [5] Feb. 02, 2017 [6],[27]        
Shares | shares 16,228 [5] 16,228 [6],[27] 16,228 [5] 16,228 [6],[27]    
Drug Discovery & Development | Tricida, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 863,000 [1],[5] $ 863,000 [2],[6]        
Investments at Fair Value $ 721,000 [5] $ 658,000 [6]        
Investment, Acquisition Date Feb. 28, 2018 [5] Feb. 28, 2018 [6]        
Shares | shares 68,816 [5] 68,816 [6] 68,816 [5] 68,816 [6]    
Drug Discovery & Development | Tricida, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 280,000 [1],[5] $ 280,000 [2],[6]        
Investments at Fair Value $ 22,000 [5] $ 20,000 [6]        
Investment, Acquisition Date Mar. 27, 2019 [5] Mar. 27, 2019 [6]        
Shares | shares 31,352 [5] 31,352 [6] 31,352 [5] 31,352 [6]    
Drug Discovery & Development | ADMA Biologics, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 295,000 [1],[5] $ 295,000 [2],[6]        
Investments at Fair Value $ 2,000 [5] $ 1,000 [6]        
Investment, Acquisition Date Dec. 21, 2012 [5] Dec. 21, 2012 [6]        
Shares | shares 89,750 [5] 89,750 [6] 89,750 [5] 89,750 [6]    
Drug Discovery & Development | Brickell Biotech, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2],[6]   $ 119,000        
Investments at Fair Value [6]   $ 0        
Investment, Acquisition Date [6]   Feb. 18, 2016        
Shares | shares [6]   9,005   9,005    
Drug Discovery & Development | Dermavant Sciences Ltd. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 101,000 [1],[18],[29],[30] $ 101,000 [2],[27],[33]        
Investments at Fair Value $ 104,000 [18],[29],[30] $ 354,000 [27],[33]        
Investment, Acquisition Date May 31, 2019 [5] May 31, 2019 [6],[27]        
Shares | shares 223,642 [18],[29],[30] 223,642 [27],[33] 223,642 [18],[29],[30] 223,642 [27],[33]    
Drug Discovery & Development | Evofem Biosciences, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 266,000 [1],[5] $ 266,000 [2],[6]        
Investments at Fair Value $ 0 [5] $ 0 [6]        
Investment, Acquisition Date Jun. 11, 2014 [5] Jun. 11, 2014 [6]        
Shares | shares 520 [5] 7,806 [6] 520 [5] 7,806 [6]    
Drug Discovery & Development | Myovant Sciences, Ltd. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 460,000 [1],[5],[29],[30] $ 460,000 [2],[6],[27]        
Investments at Fair Value $ 429,000 [5],[29],[30] $ 267,000 [6],[27]        
Investment, Acquisition Date Oct. 16, 2017 [5] Oct. 16, 2017 [6],[27]        
Shares | shares 73,710 [5],[29],[30] 73,710 [6],[27] 73,710 [5],[29],[30] 73,710 [6],[27]    
Drug Discovery & Development | Stealth Bio Therapeutics Corp. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 158,000 [1],[5],[29],[30] $ 158,000 [2],[6],[27]        
Investments at Fair Value $ 0 [5],[29],[30] $ 0 [6],[27]        
Investment, Acquisition Date Jun. 30, 2017 [5] Jun. 30, 2017 [6],[27]        
Shares | shares 500,000 [5],[29],[30] 500,000 [6],[27] 500,000 [5],[29],[30] 500,000 [6],[27]    
Drug Discovery & Development | Yumanity Therapeutics, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 110,000 [1],[5] $ 110,000 [2],[6]        
Investments at Fair Value $ 0 [5] $ 3,000 [6]        
Investment, Acquisition Date Dec. 20, 2019 [5] Dec. 20, 2019 [6]        
Shares | shares 15,414 [5] 15,414 [6] 15,414 [5] 15,414 [6]    
Drug Discovery & Development | Fresh Tracks Therapeutics, Inc. (p.k.a. Brickell Biotech, Inc.) | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5] $ 119,000          
Investments at Fair Value [5] $ 0          
Investment, Acquisition Date [5] Feb. 18, 2016          
Shares | shares [5] 200   200      
Drug Discovery & Development | Forbion Growth Opportunities Fund I C V | Investment Funds & Vehicles [Member]            
Investment Holdings [Line Items]            
Investment cost [1],[10],[29],[30] $ 2,353,000          
Investments at Fair Value [10],[29],[30] $ 2,291,000          
Investment, Acquisition Date [5] Nov. 16, 2020          
Drug Discovery & Development | Forbion Growth Opportunities Fund I I C V | Investment Funds & Vehicles [Member]            
Investment Holdings [Line Items]            
Investment cost [1],[10],[29],[30] $ 405,000          
Investments at Fair Value [10],[29],[30] $ 374,000          
Investment, Acquisition Date [5] Jun. 23, 2022          
Drug Discovery & Development | Valo Health, LLC (p.k.a. Integral Health Holdings, LLC) | Warrant Investment | Common Units            
Investment Holdings [Line Items]            
Investment cost [2]   $ 256,000        
Investments at Fair Value   $ 441,000        
Investment, Acquisition Date [6]   Jun. 15, 2020        
Shares | shares   102,216   102,216    
Drug Discovery & Development | Acacia Pharma Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 304,000 [1],[29],[30] $ 305,000 [2],[6],[27],[28]        
Investments at Fair Value $ 0 [29],[30] $ 6,000 [6],[27],[28]        
Investment, Acquisition Date Jun. 29, 2018 [5] Jun. 29, 2018 [6],[27],[28]        
Shares | shares 201,330 [29],[30] 201,330 [6],[27],[28] 201,330 [29],[30] 201,330 [6],[27],[28]    
Drug Discovery & Development | Genocea Biosciences Inc | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2],[6]   $ 2,000,000        
Investments at Fair Value [6]   $ 32,000        
Investment, Acquisition Date [6]   Nov. 20, 2014        
Shares | shares [6]   27,933   27,933    
Drug Discovery & Development | Genocea Biosciences Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2],[6]   $ 165,000        
Investments at Fair Value [6]   $ 1,000        
Investment, Acquisition Date [6]   Apr. 24, 2018        
Shares | shares [6]   41,176   41,176    
Drug Discovery & Development | Motif Bio P L C | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2],[27]   $ 282,000        
Investments at Fair Value [27]   $ 0        
Investment, Acquisition Date [6],[27]   Jan. 27, 2020        
Shares | shares [27]   121,337,041   121,337,041    
Drug Discovery & Development | Senior Secured | Chemocentryx, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date 2022-12 2022-12 2022-12 2022-12    
Investment Interest Rate [11],[27]   6.25%   6.25%    
Investment, Basis Spread, Variable Rate 3.30% [7] 3.30% [11],[27] 3.30% [7] 3.30% [11],[27]    
Investment, Interest Rate, Floor 8.05% [7] 8.05% [11],[27] 8.05% [7] 8.05% [11],[27]    
Interest Rate and Floor [11],[27]   6.25%   6.25%    
Principal Amount $ 11,451,000 [17],[29] $ 18,951,000 [27]        
Investment cost 12,677,000 [1],[17],[29] 20,036,000 [4],[27]        
Investments at Fair Value $ 12,780,000 [17],[29] $ 20,036,000 [27]        
Drug Discovery & Development | Senior Secured | Chemocentryx, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-02 2025-02 2025-02 2025-02    
Investment Interest Rate [11],[27]   7.15%   7.15%    
Investment, Basis Spread, Variable Rate 3.25% [7] 3.25% [11],[27] 3.25% [7] 3.25% [11],[27]    
Investment, Interest Rate, Floor 8.50% [7] 8.50% [11],[27] 8.50% [7] 8.50% [11],[27]    
Interest Rate and Floor [11],[27]   7.15%   7.15%    
Principal Amount $ 5,000,000 [17],[29] $ 5,000,000 [27]        
Investment cost 5,214,000 [1],[17],[29] 5,161,000 [2],[27]        
Investments at Fair Value $ 5,408,000 [17],[29] $ 5,070,000 [27]        
Drug Discovery & Development | Senior Secured | Nabriva Therapeutics | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date 2023-06   2023-06      
Investment, Basis Spread, Variable Rate [7] 4.30%   4.30%      
Investment, Interest Rate, Floor [7] 9.80%   9.80%      
Principal Amount [17],[29],[30] $ 3,077,000          
Investment cost [1],[17],[29],[30] 3,701,000          
Investments at Fair Value [17],[29],[30] $ 3,313,000          
Drug Discovery & Development | Senior Secured | Nabriva Therapeutics | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2023-06   2023-06    
Investment Interest Rate [11],[27],[28]   6.95%   6.95%    
Investment, Basis Spread, Variable Rate [11],[27],[28]   4.30%   4.30%    
Investment, Interest Rate, Floor [11],[27],[28]   9.80%   9.80%    
Interest Rate and Floor [11],[27],[28]   6.95%   6.95%    
Principal Amount [27],[28]   $ 5,000,000        
Investment cost [2],[27],[28]   5,500,000        
Investments at Fair Value [27],[28]   $ 5,459,000        
Drug Discovery & Development | Senior Secured | Akero Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-01   2027-01      
Investment, Basis Spread, Variable Rate [7] 3.65%   3.65%      
Investment, Interest Rate, Floor [7] 7.65%   7.65%      
Principal Amount [10],[29] $ 5,000,000          
Investment cost [1],[10],[29] 4,966,000          
Investments at Fair Value [10],[29] $ 4,983,000          
Drug Discovery & Development | Senior Secured | Albireo Pharma, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2024-07   2024-07    
Investment Interest Rate [11],[27]   6.95%   6.95%    
Investment, Basis Spread, Variable Rate [11],[27]   5.90%   5.90%    
Investment, Interest Rate, Floor [11],[27]   9.15%   9.15%    
Interest Rate and Floor [11],[27]   6.95%   6.95%    
Principal Amount [14],[27]   $ 10,000,000        
Investment cost [4],[14],[27]   10,229,000        
Investments at Fair Value [14],[27]   $ 10,268,000        
Drug Discovery & Development | Senior Secured | Alladapt Immunotherapeutics Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-09   2026-09      
Investment, Basis Spread, Variable Rate [7] 3.65%   3.65%      
Investment, Interest Rate, Floor [7] 8.40%   8.40%      
Principal Amount [10] $ 15,000,000          
Investment cost [1],[10] 14,858,000          
Investments at Fair Value [10] $ 14,858,000          
Drug Discovery & Development | Senior Secured | Aldeyra Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2023-10 2023-10 2023-10 2023-10    
Investment Interest Rate [11]   6.95%   6.95%    
Investment, Basis Spread, Variable Rate 3.10% [7] 3.10% [11] 3.10% [7] 3.10% [11]    
Investment, Interest Rate, Floor 8.60% [7] 8.60% [11] 8.60% [7] 8.60% [11]    
Interest Rate and Floor [11]   6.95%   6.95%    
Principal Amount $ 15,000,000 [12] $ 15,000,000        
Investment cost 15,817,000 [1],[12] 15,639,000 [4]        
Investments at Fair Value $ 15,608,000 [12] $ 15,653,000        
Drug Discovery & Development | Senior Secured | Applied Genetic Technologies Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-04 2024-04 2024-04 2024-04    
Investment Interest Rate [11]   9.75%   9.75%    
Investment, Basis Spread, Variable Rate 6.50% [7] 6.50% [11] 6.50% [7] 6.50% [11]    
Investment, Interest Rate, Floor [7] 9.75%   9.75%      
Interest Rate and Floor [11]   9.75%   9.75%    
Principal Amount $ 15,609,000 [17] $ 20,000,000        
Investment cost 16,450,000 [1],[17] 20,416,000 [4]        
Investments at Fair Value $ 16,308,000 [17] $ 20,339,000        
Drug Discovery & Development | Senior Secured | ATAI Life Sciences N.V. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-08   2026-08      
Investment, Basis Spread, Variable Rate [7] 4.55%   4.55%      
Investment, Interest Rate, Floor [7] 8.55%   8.55%      
Principal Amount [10],[29],[30] $ 10,500,000          
Investment cost [1],[10],[29],[30] 10,467,000          
Investments at Fair Value [10],[29],[30] $ 10,467,000          
Drug Discovery & Development | Senior Secured | Aveo Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-09 2024-09 2024-09 2024-09    
Investment, Basis Spread, Variable Rate 6.40% [7] 6.40% [11] 6.40% [7] 6.40% [11]    
Investment, Interest Rate, Floor 9.65% [7] 9.65% [11] 9.65% [7] 9.65% [11]    
Principal Amount $ 40,000,000 [12],[31] $ 40,000,000 [14],[32]        
Investment cost 41,439,000 [1],[12],[31] 40,842,000 [4],[14],[32]        
Investments at Fair Value $ 41,374,000 [12],[31] $ 40,776,000 [14],[32]        
Drug Discovery & Development | Senior Secured | Axsome Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-10 2026-10 2026-10 2026-10    
Investment Interest Rate [11],[27]   5.82%   5.82%    
Investment, Basis Spread, Variable Rate 5.70% [7] 5.70% [11],[27] 5.70% [7] 5.70% [11],[27]    
Investment, Interest Rate, Floor 8.95% [7] 8.95% [11],[27] 8.95% [7] 8.95% [11],[27]    
Interest Rate and Floor [11],[27]   5.82%   5.82%    
Principal Amount $ 81,725,000 [10],[12],[18],[19],[29] $ 50,000,000 [27],[33]        
Investment cost 81,388,000 [1],[10],[12],[18],[19],[29] 49,542,000 [4],[27],[33]        
Investments at Fair Value $ 79,295,000 [10],[12],[18],[19],[29] $ 48,859,000 [27],[33]        
Drug Discovery & Development | Senior Secured | Bicycle Therapeutics PLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-07 2024-10 2025-07 2024-10    
Investment Interest Rate [11],[27],[28]   5.00%   5.00%    
Investment, Basis Spread, Variable Rate 4.55% [7] 5.60% [11],[27],[28] 4.55% [7] 5.60% [11],[27],[28]    
Investment, Interest Rate, Floor 8.05% [7] 8.85% [11],[27],[28] 8.05% [7] 8.85% [11],[27],[28]    
Interest Rate and Floor [11],[27],[28]   5.00%   5.00%    
Principal Amount $ 11,500,000 [12],[18],[29],[30] $ 24,000,000 [14],[15],[27],[28],[33]        
Investment cost 11,724,000 [1],[12],[18],[29],[30] 24,271,000 [4],[14],[15],[27],[28],[33]        
Investments at Fair Value $ 11,619,000 [12],[18],[29],[30] $ 24,454,000 [14],[15],[27],[28],[33]        
Drug Discovery & Development | Senior Secured | BiomX, INC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-09 2025-09 2025-09 2025-09    
Investment, Basis Spread, Variable Rate 5.70% [7] 5.70% [11],[27],[28] 5.70% [7] 5.70% [11],[27],[28]    
Investment, Interest Rate, Floor 8.95% [7] 8.95% [11],[27],[28] 8.95% [7] 8.95% [11],[27],[28]    
Principal Amount $ 9,000,000 [12],[29],[30] $ 9,000,000 [14],[27],[28]        
Investment cost 9,125,000 [1],[12],[29],[30] 8,980,000 [4],[14],[27],[28]        
Investments at Fair Value $ 9,004,000 [12],[29],[30] $ 8,980,000 [14],[27],[28]        
Drug Discovery & Development | Senior Secured | BridgeBio Pharma, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-11 2026-11 2026-11 2026-11    
Investment, Interest Rate, Paid in Cash 9.00% [7] 9.00% [11] 9.00% [7] 9.00% [11]    
Investment Interest Rate [11]   2.00%   2.00%    
Interest Rate and Floor [11]   2.00%   2.00%    
Principal Amount $ 37,022,000 [9],[17],[18] $ 38,000,000        
Investment cost 36,694,000 [1],[9],[17],[18] 37,462,000 [4]        
Investments at Fair Value $ 33,561,000 [9],[17],[18] $ 37,462,000        
Drug Discovery & Development | Senior Secured | Cellarity, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-06 2026-06 2026-06 2026-06    
Investment Interest Rate [11]   3.75%   3.75%    
Investment, Basis Spread, Variable Rate 5.70% [7] 5.70% [11] 5.70% [7] 5.70% [11]    
Investment, Interest Rate, Floor 8.95% [7] 8.95% [11] 8.95% [7] 8.95% [11]    
Interest Rate and Floor [11]   3.75%   3.75%    
Principal Amount $ 30,000,000 [17],[31] $ 30,000,000 [32]        
Investment cost 29,734,000 [1],[17],[31] 29,422,000 [4],[32]        
Investments at Fair Value $ 29,943,000 [17],[31] $ 29,422,000 [32]        
Drug Discovery & Development | Senior Secured | Century Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-04 2024-04 2024-04 2024-04    
Investment Interest Rate [11]   3.95%   3.95%    
Investment, Basis Spread, Variable Rate 6.30% [7] 6.30% [11] 6.30% [7] 6.30% [11]    
Investment, Interest Rate, Floor 9.55% [7] 9.55% [11] 9.55% [7] 9.55% [11]    
Interest Rate and Floor [11]   3.95%   3.95%    
Principal Amount $ 10,000,000 [12] $ 10,000,000 [14]        
Investment cost 10,197,000 [1],[12] 10,075,000 [4],[14]        
Investments at Fair Value $ 10,261,000 [12] $ 10,361,000 [14]        
Drug Discovery & Development | Senior Secured | Codiak Biosciences, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-10 2025-10 2025-10 2025-10    
Investment Interest Rate [11]   5.50%   5.50%    
Investment, Basis Spread, Variable Rate 5.00% [7] 5.00% [11] 5.00% [7] 5.00% [11]    
Investment, Interest Rate, Floor 8.25% [7] 8.25% [11] 8.25% [7] 8.25% [11]    
Interest Rate and Floor [11]   5.50%   5.50%    
Principal Amount $ 25,000,000 [12] $ 25,000,000 [14]        
Investment cost 25,681,000 [1],[12] 25,459,000 [2],[14]        
Investments at Fair Value $ 25,076,000 [12] $ 25,316,000 [14]        
Drug Discovery & Development | Senior Secured | Corium, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-09 2026-09 2026-09 2026-09    
Investment Interest Rate [11]   7.75%   7.75%    
Investment, Basis Spread, Variable Rate 5.70% [7] 5.70% [11] 5.70% [7] 5.70% [11]    
Investment, Interest Rate, Floor 8.95% [7] 8.95% [11] 8.95% [7] 8.95% [11]    
Interest Rate and Floor [11]   7.75%   7.75%    
Principal Amount $ 132,675,000 [17],[19] $ 91,500,000 [21]        
Investment cost 133,069,000 [1],[17],[19] 90,997,000 [2],[21]        
Investments at Fair Value $ 135,828,000 [17],[19] $ 90,997,000 [21]        
Drug Discovery & Development | Senior Secured | Eloxx Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-04 2025-04 2025-04 2025-04    
Investment Interest Rate [11]   6.25%   6.25%    
Investment, Basis Spread, Variable Rate [7] 6.25%   6.25%      
Investment, Interest Rate, Floor 9.50% [7] 9.50% [11] 9.50% [7] 9.50% [11]    
Interest Rate and Floor [11]   6.25%   6.25%    
Principal Amount $ 12,500,000 [31] $ 12,500,000 [32]        
Investment cost 12,673,000 [1],[31] 12,443,000 [2],[32]        
Investments at Fair Value $ 12,408,000 [31] $ 12,443,000 [32]        
Drug Discovery & Development | Senior Secured | enGene, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-07 2025-07 2025-07 2025-07    
Investment Interest Rate [11],[27],[28]   6.35%   6.35%    
Investment, Basis Spread, Variable Rate 5.00% [7] 5.00% [11],[27],[28] 5.00% [7] 5.00% [11],[27],[28]    
Investment, Interest Rate, Floor [11],[27],[28]   8.25%   8.25%    
Interest Rate and Floor [11],[27],[28]   6.35%   6.35%    
Principal Amount $ 11,000,000 [17],[29],[30] $ 7,000,000 [27],[28]        
Investment cost 10,994,000 [1],[17],[29],[30] 6,858,000 [2],[27],[28]        
Investments at Fair Value $ 10,918,000 [17],[29],[30] $ 6,858,000 [27],[28]        
Drug Discovery & Development | Senior Secured | Finch Therapeutics Group, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-11   2026-11      
Investment, Basis Spread, Variable Rate [7] 4.05%   4.05%      
Investment, Interest Rate, Floor [7] 7.55%   7.55%      
Principal Amount [10] $ 15,000,000          
Investment cost [1],[10] 14,958,000          
Investments at Fair Value [10] $ 14,241,000          
Drug Discovery & Development | Senior Secured | G1 Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-11 2026-11 2026-11 2026-11    
Investment Interest Rate [11],[27]   9.86%   9.86%    
Investment, Basis Spread, Variable Rate 5.90% [7] 5.90% [11],[27] 5.90% [7] 5.90% [11],[27]    
Investment, Interest Rate, Floor 9.15% [7] 9.15% [11],[27] 9.15% [7] 9.15% [11],[27]    
Interest Rate and Floor [11],[27]   9.86%   9.86%    
Principal Amount $ 58,125,000 [10],[12],[18],[31] $ 58,125,000 [14],[15],[27],[32],[33]        
Investment cost 58,472,000 [1],[10],[12],[18],[31] 57,873,000 [2],[14],[15],[27],[32],[33]        
Investments at Fair Value $ 58,006,000 [10],[12],[18],[31] $ 57,874,000 [14],[15],[27],[32],[33]        
Drug Discovery & Development | Senior Secured | Geron Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-10 2024-10 2024-10 2024-10    
Investment Interest Rate [11],[27]   6.55%   6.55%    
Investment, Basis Spread, Variable Rate 5.75% [7] 5.75% [11],[27] 5.75% [7] 5.75% [11],[27]    
Investment, Interest Rate, Floor 9.00% [7] 9.00% [11],[27] 9.00% [7] 9.00% [11],[27]    
Interest Rate and Floor [11],[27]   6.55%   6.55%    
Principal Amount $ 18,500,000 [17],[18],[29] $ 32,500,000 [27],[33]        
Investment cost 19,003,000 [1],[17],[18],[29] 32,704,000 [2],[27],[33]        
Investments at Fair Value $ 19,059,000 [17],[18],[29] $ 32,744,000 [27],[33]        
Drug Discovery & Development | Senior Secured | Gritstone Bio, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-07   2027-07      
Investment, Basis Spread, Variable Rate [7] 3.15%   3.15%      
Investment, Interest Rate, Floor [7] 7.15%   7.15%      
Investment, Interest Rate, Paid in Kind [7] 2.00%   2.00%      
Principal Amount [9],[10] $ 15,037,000          
Investment cost [1],[9],[10] 14,989,000          
Investments at Fair Value [9],[10] $ 14,989,000          
Drug Discovery & Development | Senior Secured | Hibercell, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-05 2025-05 2025-05 2025-05    
Investment Interest Rate [11]   4.95%   4.95%    
Investment, Basis Spread, Variable Rate 5.40% [7] 5.40% [11] 5.40% [7] 5.40% [11]    
Investment, Interest Rate, Floor 8.65% [7] 8.65% [11] 8.65% [7] 8.65% [11]    
Interest Rate and Floor [11]   4.95%   4.95%    
Principal Amount $ 17,000,000 [17],[31] $ 17,000,000 [32]        
Investment cost 17,244,000 [1],[17],[31] 17,041,000 [2],[32]        
Investments at Fair Value $ 17,225,000 [17],[31] $ 17,014,000 [32]        
Drug Discovery & Development | Senior Secured | HilleVax, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-05   2027-05      
Investment, Basis Spread, Variable Rate [7] 1.05%   1.05%      
Investment, Interest Rate, Floor [7] 4.55%   4.55%      
Investment, Interest Rate, Paid in Kind [7] 2.85%   2.85%      
Principal Amount [9],[10],[31] $ 4,043,000          
Investment cost [1],[9],[10],[31] 4,043,000          
Investments at Fair Value [9],[10],[31] $ 4,044,000          
Drug Discovery & Development | Senior Secured | Iveric Bio Gene Therapy LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-08   2027-08      
Investment, Basis Spread, Variable Rate [7] 4.00%   4.00%      
Investment, Interest Rate, Floor [7] 8.75%   8.75%      
Principal Amount [10],[29] $ 24,750,000          
Investment cost [1],[10],[29] 24,530,000          
Investments at Fair Value [10],[29] $ 24,531,000          
Drug Discovery & Development | Senior Secured | Humanigen, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2025-03   2025-03    
Investment Interest Rate [11],[26],[27]   6.75%   6.75%    
Investment, Basis Spread, Variable Rate [11],[26],[27]   5.50%   5.50%    
Investment, Interest Rate, Floor [11],[26],[27]   8.75%   8.75%    
Interest Rate and Floor [11],[26],[27]   6.75%   6.75%    
Principal Amount [26],[27]   $ 20,000,000        
Investment cost [2],[26],[27]   20,235,000        
Investments at Fair Value [26],[27]   $ 19,985,000        
Drug Discovery & Development | Senior Secured | Kaleido Biosciences, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2024-01   2024-01    
Investment Interest Rate [11]   7.55%   7.55%    
Investment, Basis Spread, Variable Rate [11]   6.10%   6.10%    
Investment, Interest Rate, Floor [11]   9.35%   9.35%    
Interest Rate and Floor [11]   7.55%   7.55%    
Principal Amount [33]   $ 22,500,000        
Investment cost [2],[33]   23,505,000        
Investments at Fair Value [33]   $ 23,384,000        
Drug Discovery & Development | Senior Secured | Locus Biosciences, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-07 2025-07 2025-07 2025-07    
Investment Interest Rate [11]   4.95%   4.95%    
Investment, Basis Spread, Variable Rate 6.10% [7] 6.10% [11] 6.10% [7] 6.10% [11]    
Investment, Interest Rate, Floor 9.35% [7] 9.35% [11] 9.35% [7] 9.35% [11]    
Interest Rate and Floor [11]   4.95%   4.95%    
Principal Amount $ 8,000,000 [31] $ 8,000,000 [32]        
Investment cost 8,084,000 [1],[31] 7,977,000 [2],[32]        
Investments at Fair Value $ 8,062,000 [31] $ 7,900,000 [32]        
Drug Discovery & Development | Senior Secured | Madrigal Pharmaceutical, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-05   2026-05      
Investment, Basis Spread, Variable Rate [7] 3.95%   3.95%      
Investment, Interest Rate, Floor [7] 7.45%   7.45%      
Principal Amount [29] $ 34,000,000          
Investment cost [1],[29] 33,807,000          
Investments at Fair Value [29] $ 33,807,000          
Drug Discovery & Development | Senior Secured | Phathom Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-10 2026-10 2026-10 2026-10    
Investment Interest Rate [11],[27]   7.50%   7.50%    
Investment, Basis Spread, Variable Rate 2.25% [7] 2.25% [11],[27] 2.25% [7] 2.25% [11],[27]    
Investment, Interest Rate, Floor 5.50% [7] 5.50% [11],[27] 5.50% [7] 5.50% [11],[27]    
Investment, Interest Rate, Paid in Kind 3.35% [7] 3.35% [11],[27] 3.35% [7] 3.35% [11],[27]    
Interest Rate and Floor [11],[27]   7.50%   7.50%    
Principal Amount $ 93,978,000 [9],[10],[18],[19],[29],[31] $ 87,116,000 [15],[20],[21],[27],[32],[33]        
Investment cost 93,948,000 [1],[9],[10],[18],[19],[29],[31] 86,075,000 [2],[15],[20],[21],[27],[32],[33]        
Investments at Fair Value $ 94,006,000 [9],[10],[18],[19],[29],[31] $ 86,075,000 [15],[20],[21],[27],[32],[33]        
Drug Discovery & Development | Senior Secured | Provention Bio, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-09   2026-09      
Investment, Basis Spread, Variable Rate [7] 2.70%   2.70%      
Investment, Interest Rate, Floor [7] 8.20%   8.20%      
Principal Amount $ 25,000,000          
Investment cost [1] 24,552,000          
Investments at Fair Value $ 24,552,000          
Drug Discovery & Development | Senior Secured | Redshift Bioanalytics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-01   2026-01      
Investment, Basis Spread, Variable Rate [7] 4.25%   4.25%      
Investment, Interest Rate, Floor [7] 7.50%   7.50%      
Principal Amount [31] $ 5,000,000          
Investment cost [1],[31] 4,936,000          
Investments at Fair Value [31] $ 4,935,000          
Drug Discovery & Development | Senior Secured | Scynexis, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-03 2025-03 2025-03 2025-03    
Investment Interest Rate [11]   3.95%   3.95%    
Investment, Basis Spread, Variable Rate 5.80% [7] 5.80% [11] 5.80% [7] 5.80% [11]    
Investment, Interest Rate, Floor 9.05% [7] 9.05% [11] 9.05% [7] 9.05% [11]    
Interest Rate and Floor [11]   3.95%   3.95%    
Principal Amount $ 18,667,000 [17],[18] $ 16,000,000        
Investment cost 18,592,000 [1],[17],[18] 15,826,000 [2]        
Investments at Fair Value $ 18,524,000 [17],[18] $ 15,778,000        
Drug Discovery & Development | Senior Secured | Seres Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-10 2023-11 2024-10 2023-11    
Investment Interest Rate [11]   4.85%   4.85%    
Investment, Basis Spread, Variable Rate 6.40% [7] 4.40% [11] 6.40% [7] 4.40% [11]    
Investment, Interest Rate, Floor 9.65% [7] 9.65% [11] 9.65% [7] 9.65% [11]    
Interest Rate and Floor [11]   4.85%   4.85%    
Principal Amount $ 37,500,000 [17],[18] $ 24,051,000        
Investment cost 38,509,000 [1],[17],[18] 24,777,000 [2]        
Investments at Fair Value $ 38,657,000 [17],[18] $ 25,183,000        
Drug Discovery & Development | Senior Secured | Syndax Pharmaceutics Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2024-04   2024-04    
Investment Interest Rate [11]   4.99%   4.99%    
Investment, Basis Spread, Variable Rate [11]   6.00%   6.00%    
Investment, Interest Rate, Floor [11]   9.25%   9.25%    
Interest Rate and Floor [11]   4.99%   4.99%    
Principal Amount [15],[33]   $ 20,000,000        
Investment cost [2],[15],[33]   20,646,000        
Investments at Fair Value [15],[33]   $ 20,653,000        
Drug Discovery & Development | Senior Secured | Tarsus Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-02   2027-02      
Investment, Basis Spread, Variable Rate [7] 5.20%   5.20%      
Investment, Interest Rate, Floor [7] 8.45%   8.45%      
Principal Amount [10],[17],[29] $ 8,250,000          
Investment cost [1],[10],[17],[29] 8,255,000          
Investments at Fair Value [10],[17],[29] $ 8,388,000          
Drug Discovery & Development | Senior Secured | TG Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-01 2026-01 2026-01 2026-01    
Investment Interest Rate [11],[27]   5.95%   5.95%    
Investment, Basis Spread, Variable Rate 2.15% [7] 2.15% [11],[27] 2.15% [7] 2.15% [11],[27]    
Investment, Interest Rate, Floor 5.40% [7] 5.40% [11],[27] 5.40% [7] 5.40% [11],[27]    
Investment, Interest Rate, Paid in Kind [7] 3.45%   3.45%      
Interest Rate and Floor [11],[27]   5.95%   5.95%    
Principal Amount $ 47,567,000 [9],[12],[18],[29] $ 51,450,000 [27]        
Investment cost 47,267,000 [1],[9],[12],[18],[29] 50,470,000 [2],[27]        
Investments at Fair Value $ 47,137,000 [9],[12],[18],[29] $ 50,470,000 [27]        
Drug Discovery & Development | Senior Secured | Uni Qure B V | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-12 2025-12 2025-12 2025-12    
Investment Interest Rate [11],[27],[28]   7.28%   7.28%    
Investment, Basis Spread, Variable Rate 4.70% [7] 4.70% [11],[27],[28] 4.70% [7] 4.70% [11],[27],[28]    
Investment, Interest Rate, Floor 7.95% [7] 7.95% [11],[27],[28] 7.95% [7] 7.95% [11],[27],[28]    
Interest Rate and Floor [11],[27],[28]   7.28%   7.28%    
Principal Amount $ 70,000,000 [12],[18],[19],[29],[30] $ 77,500,000 [14],[21],[27],[28],[33]        
Investment cost 72,015,000 [1],[12],[18],[19],[29],[30] 78,755,000 [2],[14],[21],[27],[28],[33]        
Investments at Fair Value $ 73,205,000 [12],[18],[19],[29],[30] $ 78,755,000 [14],[21],[27],[28],[33]        
Drug Discovery & Development | Senior Secured | Unity Biotechnology Inc | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-08 2024-08 2024-08 2024-08    
Investment Interest Rate [11],[26]   6.25%   6.25%    
Investment, Basis Spread, Variable Rate 6.10% [7] 6.10% [11],[26] 6.10% [7] 6.10% [11],[26]    
Investment, Interest Rate, Floor 9.35% [7] 9.35% [11],[26] 9.35% [7] 9.35% [11],[26]    
Interest Rate and Floor [11],[26]   6.25%   6.25%    
Principal Amount $ 20,000,000 [17] $ 22,701,000 [26]        
Investment cost 20,990,000 [1],[17] 23,293,000 [2],[26]        
Investments at Fair Value $ 20,844,000 [17] $ 23,627,000 [26]        
Drug Discovery & Development | Senior Secured | Valo Health L L C | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-05 2024-05 2024-05 2024-05    
Investment Interest Rate [11]   3.85%   3.85%    
Investment, Basis Spread, Variable Rate 6.45% [7] 6.45% [11] 6.45% [7] 6.45% [11]    
Investment, Interest Rate, Floor 9.70% [7] 9.70% [11] 9.70% [7] 9.70% [11]    
Interest Rate and Floor [11]   3.85%   3.85%    
Principal Amount $ 9,583,000 [12],[17] $ 11,500,000 [14]        
Investment cost 9,805,000 [1],[12],[17] 11,547,000 [2],[14]        
Investments at Fair Value $ 9,760,000 [12],[17] $ 11,492,000 [14]        
Drug Discovery & Development | Senior Secured | Viridian Therapeutics Inc | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-10   2026-10      
Investment, Basis Spread, Variable Rate [7] 4.20%   4.20%      
Investment, Interest Rate, Floor [7] 7.45%   7.45%      
Principal Amount [10],[17],[29] $ 2,000,000          
Investment cost [1],[10],[17],[29] 2,004,000          
Investments at Fair Value [10],[17],[29] $ 1,969,000          
Drug Discovery & Development | Senior Secured | X Four Pharmaceuticals Inc | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-07 2024-07 2024-07 2024-07    
Investment Interest Rate [11]   8.80%   8.80%    
Investment, Basis Spread, Variable Rate 3.75% [7] 3.75% [11] 3.75% [7] 3.75% [11]    
Investment, Interest Rate, Floor 8.75% [7] 8.75% [11] 8.75% [7] 8.75% [11]    
Interest Rate and Floor [11]   8.80%   8.80%    
Principal Amount $ 32,500,000 [12],[17],[18] $ 32,500,000 [14],[33]        
Investment cost 33,464,000 [1],[12],[17],[18] 34,140,000 [2],[14],[33]        
Investments at Fair Value $ 33,291,000 [12],[17],[18] $ 34,085,000 [14],[33]        
Drug Discovery & Development | Senior Secured | Yumanity Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2024-01   2024-01    
Investment Interest Rate [11]   5.92%   5.92%    
Investment, Basis Spread, Variable Rate [11]   4.00%   4.00%    
Investment, Interest Rate, Floor [11]   8.75%   8.75%    
Interest Rate and Floor [11]   5.92%   5.92%    
Principal Amount   $ 12,732,000        
Investment cost [2]   13,256,000        
Investments at Fair Value   $ 13,187,000        
Drug Discovery & Development | Senior Secured | Center for Breakthrough Medicines Holdings, LLC [Member] | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2023-05   2023-05    
Investment Interest Rate [11]   7.50%   7.50%    
Investment, Basis Spread, Variable Rate [11]   5.50%   5.50%    
Investment, Interest Rate, Floor [11]   8.75%   8.75%    
Interest Rate and Floor [11]   7.50%   7.50%    
Principal Amount   $ 5,000,000        
Investment cost [4]   5,005,000        
Investments at Fair Value   $ 5,005,000        
Drug Discovery & Development | Senior Secured | Floor Rate | enGene, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment, Interest Rate, Floor [7] 8.25%   8.25%      
Drug Discovery & Development | Senior Secured | Exit Fee | Chemocentryx, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.25%   6.25%      
Interest Rate and Floor [7] 6.25%   6.25%      
Drug Discovery & Development | Senior Secured | Exit Fee | Chemocentryx, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 7.15%   7.15%      
Interest Rate and Floor [7] 7.15%   7.15%      
Drug Discovery & Development | Senior Secured | Exit Fee | Nabriva Therapeutics | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 9.95%   9.95%      
Interest Rate and Floor [7] 9.95%   9.95%      
Drug Discovery & Development | Senior Secured | Exit Fee | Akero Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.85%   5.85%      
Interest Rate and Floor [7] 5.85%   5.85%      
Drug Discovery & Development | Senior Secured | Exit Fee | Alladapt Immunotherapeutics Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.30%   5.30%      
Interest Rate and Floor [7] 5.30%   5.30%      
Drug Discovery & Development | Senior Secured | Exit Fee | Aldeyra Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.95%   6.95%      
Interest Rate and Floor [7] 6.95%   6.95%      
Drug Discovery & Development | Senior Secured | Exit Fee | Applied Genetic Technologies Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate 6.95% [7] 6.95% [11] 6.95% [7] 6.95% [11]    
Interest Rate and Floor 6.95% [7] 6.95% [11] 6.95% [7] 6.95% [11]    
Drug Discovery & Development | Senior Secured | Exit Fee | ATAI Life Sciences N.V. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.95%   6.95%      
Interest Rate and Floor [7] 6.95%   6.95%      
Drug Discovery & Development | Senior Secured | Exit Fee | Aveo Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate 6.95% [7] 6.95% [11] 6.95% [7] 6.95% [11]    
Interest Rate and Floor 6.95% [7] 6.95% [11] 6.95% [7] 6.95% [11]    
Drug Discovery & Development | Senior Secured | Exit Fee | Axsome Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.31%   5.31%      
Interest Rate and Floor [7] 5.31%   5.31%      
Drug Discovery & Development | Senior Secured | Exit Fee | Bicycle Therapeutics PLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.00%   5.00%      
Interest Rate and Floor [7] 5.00%   5.00%      
Drug Discovery & Development | Senior Secured | Exit Fee | BiomX, INC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate 6.55% [7] 6.55% [11],[27],[28] 6.55% [7] 6.55% [11],[27],[28]    
Interest Rate and Floor 6.55% [7] 6.55% [11],[27],[28] 6.55% [7] 6.55% [11],[27],[28]    
Drug Discovery & Development | Senior Secured | Exit Fee | BridgeBio Pharma, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 2.00%   2.00%      
Interest Rate and Floor [7] 2.00%   2.00%      
Drug Discovery & Development | Senior Secured | Exit Fee | Cellarity, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.75%   3.75%      
Interest Rate and Floor [7] 3.75%   3.75%      
Drug Discovery & Development | Senior Secured | Exit Fee | Century Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.95%   3.95%      
Interest Rate and Floor [7] 3.95%   3.95%      
Drug Discovery & Development | Senior Secured | Exit Fee | Codiak Biosciences, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.50%   5.50%      
Interest Rate and Floor [7] 5.50%   5.50%      
Drug Discovery & Development | Senior Secured | Exit Fee | Corium, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 7.75%   7.75%      
Interest Rate and Floor [7] 7.75%   7.75%      
Drug Discovery & Development | Senior Secured | Exit Fee | Eloxx Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate 6.55% [7] 6.55% [11] 6.55% [7] 6.55% [11]    
Interest Rate and Floor 6.55% [7] 6.55% [11] 6.55% [7] 6.55% [11]    
Drug Discovery & Development | Senior Secured | Exit Fee | enGene, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.35%   6.35%      
Interest Rate and Floor [7] 6.35%   6.35%      
Drug Discovery & Development | Senior Secured | Exit Fee | Finch Therapeutics Group, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.50%   5.50%      
Interest Rate and Floor [7] 5.50%   5.50%      
Drug Discovery & Development | Senior Secured | Exit Fee | G1 Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 9.86%   9.86%      
Interest Rate and Floor [7] 9.86%   9.86%      
Drug Discovery & Development | Senior Secured | Exit Fee | Geron Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.55%   6.55%      
Interest Rate and Floor [7] 6.55%   6.55%      
Drug Discovery & Development | Senior Secured | Exit Fee | Gritstone Bio, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.75%   5.75%      
Interest Rate and Floor [7] 5.75%   5.75%      
Drug Discovery & Development | Senior Secured | Exit Fee | Hibercell, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.95%   4.95%      
Interest Rate and Floor [7] 4.95%   4.95%      
Drug Discovery & Development | Senior Secured | Exit Fee | HilleVax, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 7.15%   7.15%      
Interest Rate and Floor [7] 7.15%   7.15%      
Drug Discovery & Development | Senior Secured | Exit Fee | Iveric Bio Gene Therapy LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.25%   4.25%      
Interest Rate and Floor [7] 4.25%   4.25%      
Drug Discovery & Development | Senior Secured | Exit Fee | Locus Biosciences, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.95%   4.95%      
Interest Rate and Floor [7] 4.95%   4.95%      
Drug Discovery & Development | Senior Secured | Exit Fee | Madrigal Pharmaceutical, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.35%   5.35%      
Interest Rate and Floor [7] 5.35%   5.35%      
Drug Discovery & Development | Senior Secured | Exit Fee | Phathom Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 7.50%   7.50%      
Interest Rate and Floor [7] 7.50%   7.50%      
Drug Discovery & Development | Senior Secured | Exit Fee | Provention Bio, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.60%   6.60%      
Interest Rate and Floor [7] 6.60%   6.60%      
Drug Discovery & Development | Senior Secured | Exit Fee | Redshift Bioanalytics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.80%   3.80%      
Interest Rate and Floor [7] 3.80%   3.80%      
Drug Discovery & Development | Senior Secured | Exit Fee | Scynexis, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.95%   3.95%      
Interest Rate and Floor [7] 3.95%   3.95%      
Drug Discovery & Development | Senior Secured | Exit Fee | Seres Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.98%   4.98%      
Interest Rate and Floor [7] 4.98%   4.98%      
Drug Discovery & Development | Senior Secured | Exit Fee | Tarsus Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.75%   4.75%      
Interest Rate and Floor [7] 4.75%   4.75%      
Drug Discovery & Development | Senior Secured | Exit Fee | TG Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.95%   5.95%      
Interest Rate and Floor [7] 5.95%   5.95%      
Drug Discovery & Development | Senior Secured | Exit Fee | Uni Qure B V | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 7.28%   7.28%      
Interest Rate and Floor [7] 7.28%   7.28%      
Drug Discovery & Development | Senior Secured | Exit Fee | Unity Biotechnology Inc | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.25%   6.25%      
Interest Rate and Floor [7] 6.25%   6.25%      
Drug Discovery & Development | Senior Secured | Exit Fee | Valo Health L L C | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.85%   3.85%      
Interest Rate and Floor [7] 3.85%   3.85%      
Drug Discovery & Development | Senior Secured | Exit Fee | Viridian Therapeutics Inc | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.76%   4.76%      
Interest Rate and Floor [7] 4.76%   4.76%      
Drug Discovery & Development | Senior Secured | Exit Fee | X Four Pharmaceuticals Inc | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 8.80%   8.80%      
Interest Rate and Floor [7] 8.80%   8.80%      
Drug Discovery & Development | Senior Secured | Cap Rate | Alladapt Immunotherapeutics Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 10.90%   10.90%      
Interest Rate and Floor [7] 10.90%   10.90%      
Drug Discovery & Development | Senior Secured | Cap Rate | Aveo Pharmaceuticals, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 15.00%   15.00%      
Interest Rate and Floor [7] 15.00%   15.00%      
Drug Discovery & Development | Senior Secured | Cap Rate | Axsome Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 10.70%   10.70%      
Interest Rate and Floor [7] 10.70%   10.70%      
Drug Discovery & Development | Senior Secured | Cap Rate | Bicycle Therapeutics PLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 9.05%   9.05%      
Interest Rate and Floor [7] 9.05%   9.05%      
Drug Discovery & Development | Senior Secured | Cap Rate | Finch Therapeutics Group, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 8.80%   8.80%      
Interest Rate and Floor [7] 8.80%   8.80%      
Drug Discovery & Development | Senior Secured | Cap Rate | Gritstone Bio, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 8.65%   8.65%      
Interest Rate and Floor [7] 8.65%   8.65%      
Drug Discovery & Development | Senior Secured | Cap Rate | HilleVax, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.05%   6.05%      
Interest Rate and Floor [7] 6.05%   6.05%      
Drug Discovery & Development | Senior Secured | Cap Rate | Iveric Bio Gene Therapy LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 10.25%   10.25%      
Interest Rate and Floor [7] 10.25%   10.25%      
Drug Discovery & Development | Senior Secured | Cap Rate | Viridian Therapeutics Inc | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 8.95%   8.95%      
Interest Rate and Floor [7] 8.95%   8.95%      
Drug Discovery & Development | Senior Secured Tranche A [Member] | TG Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment, Interest Rate, Paid in Kind [11],[27]   3.45%   3.45%    
Drug Discovery & Development | Debt Investments            
Investment Holdings [Line Items]            
Investment cost $ 1,056,335,000 [1] $ 936,457,000 [2]        
Investments at Fair Value 1,052,244,000 935,964,000        
Drug Delivery            
Investment Holdings [Line Items]            
Investments at Fair Value 90,000 368,000        
Drug Delivery | Equity            
Investment Holdings [Line Items]            
Investment cost 3,638,000 [1] 3,638,000 [2]        
Investments at Fair Value   305,000        
Drug Delivery | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 465,000 [1] 465,000 [2]        
Investments at Fair Value 0 63,000        
Drug Delivery | AcelRx Pharmaceuticals, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost 1,329,000 [1],[5] 1,329,000 [2],[6]        
Investments at Fair Value $ 37,000 [5] $ 99,000 [6]        
Investment, Acquisition Date Dec. 10, 2018 [5] Dec. 10, 2018 [6]        
Shares | shares 176,730 [5] 176,730 [6] 176,730 [5] 176,730 [6]    
Drug Delivery | Aytu BioScience, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,500,000 [1],[5] $ 1,500,000 [2],[6]        
Investments at Fair Value $ 3,000 [5] $ 18,000 [6]        
Investment, Acquisition Date Mar. 28, 2014 [5] Mar. 28, 2014 [6]        
Shares | shares 13,600 [5] 13,600 [6] 13,600 [5] 13,600 [6]    
Drug Delivery | BioQ Pharma Incorporated | Equity | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost $ 500,000 [1] $ 500,000 [2]        
Investments at Fair Value $ 43,000 $ 168,000        
Investment, Acquisition Date Dec. 08, 2015 [5] Dec. 08, 2015 [6]        
Shares | shares 165,000 165,000 165,000 165,000    
Drug Delivery | BioQ Pharma Incorporated | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,000 [1] $ 1,000 [2]        
Investments at Fair Value $ 0 $ 62,000        
Investment, Acquisition Date Oct. 27, 2014 [5] Oct. 27, 2014 [6]        
Shares | shares 459,183 459,183 459,183 459,183    
Drug Delivery | PDS Biotechnology Corporation | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5] $ 309,000          
Investments at Fair Value [5] $ 7,000          
Investment, Acquisition Date [5] Apr. 06, 2015          
Shares | shares [5] 2,498   2,498      
Drug Delivery | PDS Biotechnology Corporation | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 390,000 [1],[5] $ 390,000 [2],[6]        
Investments at Fair Value $ 0 [5] $ 1,000 [6]        
Investment, Acquisition Date Aug. 28, 2014 [5] Aug. 28, 2014 [6]        
Shares | shares 3,929 [5] 3,929 [6] 3,929 [5] 3,929 [6]    
Drug Delivery | Aerami Therapeutics Holdings, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 74,000 [1] $ 74,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Sep. 30, 2015 [5] Sep. 30, 2015 [6]        
Shares | shares 110,882 110,882 110,882 110,882    
Drug Delivery | PDS Biotechnology Corporation (p.k.a. Edge Therapeutics, Inc.) | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2],[6]   $ 309,000        
Investments at Fair Value [6]   $ 20,000        
Investment, Acquisition Date [6]   Apr. 06, 2015        
Shares | shares [6]   2,498   2,498    
Healthcare Services Other            
Investment Holdings [Line Items]            
Investments at Fair Value $ 203,599,000 $ 121,003,000        
Healthcare Services Other | Equity            
Investment Holdings [Line Items]            
Investment cost 6,782,000 [1] 6,781,000 [2]        
Investments at Fair Value 3,198,000 7,364,000        
Healthcare Services Other | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost [1] 697,000          
Investments at Fair Value 521,000          
Healthcare Services Other | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 156,619,000 [1] 113,724,000 [2]        
Investments at Fair Value 155,925,000 113,639,000        
Healthcare Services Other | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost [1] 43,955,000          
Investments at Fair Value 43,955,000          
Healthcare Services Other | Carbon Health Technologies, Inc. | Equity | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost 1,688,000 [1] 1,687,000 [2]        
Investments at Fair Value $ 836,000 $ 1,864,000        
Investment, Acquisition Date Mar. 30, 2021 [5] Mar. 30, 2021 [6]        
Shares | shares 217,880 217,880 217,880 217,880    
Healthcare Services Other | Elation Health, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 583,000          
Investments at Fair Value $ 501,000          
Investment, Acquisition Date [5] Sep. 12, 2022          
Shares | shares 362,837   362,837      
Healthcare Services Other | 23andMe, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 5,094,000 [1],[5] $ 5,094,000 [2],[6]        
Investments at Fair Value $ 2,362,000 [5] $ 5,500,000 [6]        
Investment, Acquisition Date Mar. 11, 2019 [5] Mar. 11, 2019 [6]        
Shares | shares 825,732 [5] 825,732 [6] 825,732 [5] 825,732 [6]    
Healthcare Services Other | Vida Health, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 114,000          
Investments at Fair Value $ 20,000          
Investment, Acquisition Date [5] Mar. 28, 2022          
Shares | shares 100,618   100,618      
Healthcare Services Other | Senior Secured | Better Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-08 2025-08 2025-08 2025-08    
Investment Interest Rate   5.95%   5.95%    
Investment, Basis Spread, Variable Rate 5.70% [7] 5.70% 5.70% [7] 5.70%    
Investment, Interest Rate, Floor 8.95% [7] 8.95% 8.95% [7] 8.95%    
Interest Rate and Floor   5.95%   5.95%    
Principal Amount $ 12,000,000 [31] $ 8,000,000 [15],[32]        
Investment cost 12,093,000 [1],[31] 7,966,000 [2],[15],[32]        
Investments at Fair Value $ 11,996,000 [31] $ 7,966,000 [15],[32]        
Healthcare Services Other | Senior Secured | Blue Sprig Pediatrics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-11 2026-11 2026-11 2026-11    
Investment, Basis Spread, Variable Rate 5.00% [7] 5.00% 5.00% [7] 5.00%    
Investment, Interest Rate, Floor 6.00% [7] 6.00% 6.00% [7] 6.00%    
Investment, Interest Rate, Paid in Kind [7] 4.45%   4.45%      
Principal Amount $ 40,949,000 [9],[10],[12],[17] $ 25,022,000 [15],[20]        
Investment cost 40,403,000 [1],[9],[10],[12],[17] 24,653,000 [2],[15],[20]        
Investments at Fair Value $ 39,332,000 [9],[10],[12],[17] $ 24,653,000 [15],[20]        
Healthcare Services Other | Senior Secured | Carbon Health Technologies, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-03 2025-03 2025-03 2025-03    
Investment Interest Rate   4.61%   4.61%    
Investment, Basis Spread, Variable Rate 5.60% [7] 5.60% 5.60% [7] 5.60%    
Investment, Interest Rate, Floor 8.85% [7] 8.85% 8.85% [7] 8.85%    
Interest Rate and Floor   4.61%   4.61%    
Principal Amount $ 46,125,000 [8],[10],[12],[17],[18] $ 46,125,000 [15],[23]        
Investment cost 46,399,000 [1],[8],[10],[12],[17],[18] 45,964,000 [2],[15],[23]        
Investments at Fair Value $ 46,158,000 [8],[10],[12],[17],[18] $ 45,964,000 [15],[23]        
Healthcare Services Other | Senior Secured | Equality Health, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-02 2026-02 2026-02 2026-02    
Investment Interest Rate   1.55%   1.55%    
Investment, Basis Spread, Variable Rate 6.25% [7] 6.25% 6.25% [7] 6.25%    
Investment, Interest Rate, Floor 9.50% [7] 9.50% 9.50% [7] 9.50%    
Investment, Interest Rate, Paid in Kind [7] 1.55%   1.55%      
Interest Rate and Floor   1.55%   1.55%    
Principal Amount $ 53,388,000 [9],[18] $ 35,444,000 [15],[20],[33]        
Investment cost 52,928,000 [1],[9],[18] 35,141,000 [2],[15],[20],[33]        
Investments at Fair Value $ 53,644,000 [9],[18] 35,056,000 [15],[20],[33]        
Healthcare Services Other | Senior Secured | Elation Health, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-03   2026-03      
Investment, Basis Spread, Variable Rate [7] 4.25%   4.25%      
Investment, Interest Rate, Floor [7] 9.00%   9.00%      
Investment, Interest Rate, Paid in Kind [7] 1.95%   1.95%      
Principal Amount [8],[10] $ 5,000,000          
Investment cost [1],[8],[10] 4,796,000          
Investments at Fair Value [8],[10] $ 4,795,000          
Healthcare Services Other | Senior Secured | Oak Street Health, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment, Basis Spread, Variable Rate [7] 2.45%   2.45%      
Investment, Interest Rate, Floor [7] 7.95%   7.95%      
Principal Amount [10],[29] $ 44,250,000          
Healthcare Services Other | Senior Secured | Oak Street Health, Inc. | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-10   2027-10      
Investment, Interest Rate, Paid in Kind [7] 1.00%   1.00%      
Investment cost [1],[10],[29] $ 43,955,000          
Investments at Fair Value [10],[29] $ 43,955,000          
Healthcare Services Other | Senior Secured | Exit Fee | Better Therapeutics, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.95%   5.95%      
Interest Rate and Floor [7] 5.95%   5.95%      
Healthcare Services Other | Senior Secured | Exit Fee | Carbon Health Technologies, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.61%   4.61%      
Interest Rate and Floor [7] 4.61%   4.61%      
Healthcare Services Other | Senior Secured | Exit Fee | Elation Health, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.95%   3.95%      
Interest Rate and Floor [7] 3.95%   3.95%      
Healthcare Services Other | Senior Secured | Cap Rate | Oak Street Health, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 9.45%   9.45%      
Interest Rate and Floor [7] 9.45%   9.45%      
Healthcare Services Other | Debt Investments            
Investment Holdings [Line Items]            
Investment cost $ 200,574,000 [1] 113,724,000 [2]        
Investments at Fair Value 199,880,000 113,639,000        
Information Services            
Investment Holdings [Line Items]            
Investments at Fair Value 59,735,000 74,417,000        
Information Services | Equity            
Investment Holdings [Line Items]            
Investment cost 4,440,000 [1] 4,440,000 [2]        
Investments at Fair Value 7,579,000 9,414,000        
Information Services | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 680,000 [1] 645,000 [2]        
Investments at Fair Value 416,000 557,000        
Information Services | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 52,386,000 [1] 64,773,000 [2]        
Investments at Fair Value 51,740,000 64,446,000        
Information Services | Capella Space Corp. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost 207,000 [1],[31] 207,000 [2],[32]        
Investments at Fair Value $ 50,000 [31] $ 139,000 [32]        
Investment, Acquisition Date Oct. 21, 2021 [5] Oct. 21, 2021 [6]        
Shares | shares 176,200 [31] 176,200 [32] 176,200 [31] 176,200 [32]    
Information Services | Signal Media Limited | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[29],[30] $ 35,000          
Investments at Fair Value [29],[30] $ 21,000          
Investment, Acquisition Date [5] Jun. 29, 2022          
Shares | shares [29],[30] 94,857   94,857      
Information Services | Yipit, LLC | Equity | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost $ 3,825,000 [1] $ 3,825,000 [2]        
Investments at Fair Value $ 2,648,000 $ 3,825,000        
Investment, Acquisition Date Dec. 30, 2021 [5] Dec. 30, 2021 [6]        
Shares | shares 41,021 41,021 41,021 41,021    
Information Services | Planet Labs, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 615,000 [1],[5] $ 615,000 [2]        
Investments at Fair Value $ 2,975,000 [5] $ 3,369,000        
Investment, Acquisition Date Jun. 21, 2019 [5] Jun. 21, 2019 [6]        
Shares | shares 547,880 [5] 547,880 547,880 [5] 547,880    
Information Services | Zeta Global Corp. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 0 [1],[5] $ 0 [2],[6],[34]        
Investments at Fair Value $ 1,956,000 [5] $ 2,220,000 [6],[34]        
Investment, Acquisition Date Nov. 20, 2007 [5] Nov. 20, 2007 [6]        
Shares | shares 295,861 [5] 295,861 [6],[34] 295,861 [5] 295,861 [6],[34]    
Information Services | I N M O B I Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 82,000 [1],[29],[30] $ 82,000 [2],[27]        
Investments at Fair Value $ 0 [29],[30] $ 0 [27]        
Investment, Acquisition Date Nov. 19, 2014 [5] Nov. 19, 2014 [6],[27]        
Shares | shares 65,587 [29],[30] 65,587 [27] 65,587 [29],[30] 65,587 [27]    
Information Services | NetBase Solutions, Inc. | Warrant Investment | Preferred Series 1            
Investment Holdings [Line Items]            
Investment cost $ 356,000 [1] $ 356,000 [2]        
Investments at Fair Value $ 345,000 $ 418,000        
Investment, Acquisition Date Aug. 22, 2017 [5] Aug. 22, 2017 [6]        
Shares | shares 60,000 60,000 60,000 60,000    
Information Services | Senior Secured | Capella Space Corp. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-11 2024-11 2024-11 2024-11    
Investment Interest Rate   4.00%   4.00%    
Investment, Basis Spread, Variable Rate 5.00% [7] 5.00% 5.00% [7] 5.00%    
Investment, Interest Rate, Floor 8.25% [7] 8.25% 8.25% [7] 8.25%    
Investment, Interest Rate, Paid in Kind 1.10% [7] 1.10% 1.10% [7] 1.10%    
Interest Rate and Floor   4.00%   4.00%    
Principal Amount $ 20,193,000 [8],[9],[31] $ 20,025,000 [20],[23],[32]        
Investment cost 20,302,000 [1],[8],[9],[31] 19,751,000 [2],[20],[23],[32]        
Investments at Fair Value $ 20,219,000 [8],[9],[31] $ 19,424,000 [20],[23],[32]        
Information Services | Senior Secured | Signal Media Limited | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-06   2025-06      
Investment, Basis Spread, Variable Rate [7] 5.50%   5.50%      
Investment, Interest Rate, Floor [7] 9.00%   9.00%      
Principal Amount [10],[29],[30] $ 750,000          
Investment cost [1],[10],[29],[30] 739,000          
Investments at Fair Value [10],[29],[30] $ 739,000          
Information Services | Senior Secured | Yipit, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-09 2026-09 2026-09 2026-09    
Investment, Basis Spread, Variable Rate 9.08% [7] 9.08% 9.08% [7] 9.08%    
Investment, Interest Rate, Floor 10.08% [7] 10.08% 10.08% [7] 10.08%    
Principal Amount $ 31,875,000 [10],[13] $ 45,900,000 [15],[16]        
Investment cost 31,345,000 [1],[10],[13] 45,022,000 [2],[15],[16]        
Investments at Fair Value $ 30,782,000 [10],[13] 45,022,000 [15],[16]        
Information Services | Senior Secured | Exit Fee | Capella Space Corp. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 7.00%   7.00%      
Interest Rate and Floor [7] 7.00%   7.00%      
Information Services | Senior Secured | Exit Fee | Signal Media Limited | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.45%   3.45%      
Interest Rate and Floor [7] 3.45%   3.45%      
Information Services | Senior Secured | Cap Rate | Signal Media Limited | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 12.00%   12.00%      
Interest Rate and Floor [7] 12.00%   12.00%      
Information Services | Debt Investments            
Investment Holdings [Line Items]            
Investment cost $ 52,386,000 [1] 64,773,000 [2]        
Investments at Fair Value 51,740,000 64,446,000        
Internet Consumer And Business Services            
Investment Holdings [Line Items]            
Investments at Fair Value 489,968,000 395,506,000        
Internet Consumer And Business Services | Equity            
Investment Holdings [Line Items]            
Investment cost 22,058,000 [1] 22,151,000 [2]        
Investments at Fair Value 15,377,000 35,331,000        
Internet Consumer And Business Services | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 6,110,000 [1] 4,992,000 [2]        
Investments at Fair Value 5,800,000 10,212,000        
Internet Consumer And Business Services | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment cost 82,481,000 [1] 22,164,000 [2]        
Investments at Fair Value 82,481,000 22,164,000        
Internet Consumer And Business Services | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 384,097,000 [1] 341,001,000 [2]        
Investments at Fair Value 365,957,000 327,799,000        
Internet Consumer And Business Services | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost [1] 21,252,000          
Investments at Fair Value 20,354,000          
Internet Consumer And Business Services | Fulfil Solutions Inc [Member] | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] 325,000          
Investments at Fair Value $ 199,000          
Investment, Acquisition Date [5] Jul. 29, 2022          
Shares | shares 84,995   84,995      
Internet Consumer And Business Services | SeatGeek, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 842,000 [1],[19] 842,000 [2]        
Investments at Fair Value $ 1,692,000 [19] $ 1,140,000        
Investment, Acquisition Date Jun. 12, 2019 [5] Jun. 12, 2019 [6]        
Shares | shares 1,379,761 [19] 1,379,761 1,379,761 [19] 1,379,761    
Internet Consumer And Business Services | Carwow LTD | Equity | Preferred Series D-4            
Investment Holdings [Line Items]            
Investment cost $ 1,151,000 [1],[29],[30] $ 1,151,000 [2],[27],[28]        
Investments at Fair Value $ 216,000 [29],[30] $ 608,000 [27],[28]        
Investment, Acquisition Date Dec. 15, 2021 [5] Dec. 15, 2021 [6],[27],[28]        
Shares | shares 199,742 [29],[30] 199,742 [27],[28] 199,742 [29],[30] 199,742 [27],[28]    
Internet Consumer And Business Services | Carwow LTD | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 164,000 [1],[29],[30] $ 164,000 [2],[27],[28]        
Investments at Fair Value $ 33,000 [29],[30] $ 160,000 [27],[28]        
Investment, Acquisition Date Dec. 14, 2021 [5] Dec. 14, 2021 [6],[27],[28]        
Shares | shares 174,163 [29],[30] 174,163 [27],[28] 174,163 [29],[30] 174,163 [27],[28]    
Internet Consumer And Business Services | Convoy, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[19] $ 974,000          
Investments at Fair Value [19] $ 582,000          
Investment, Acquisition Date [5] Mar. 30, 2022          
Shares | shares [19] 165,456   165,456      
Internet Consumer And Business Services | Rhino Labs Incorporation | Equity | Preferred Series B-2            
Investment Holdings [Line Items]            
Investment cost [1] $ 1,000,000          
Investments at Fair Value $ 866,000          
Investment, Acquisition Date [5] Jan. 24, 2022          
Shares | shares 7,063   7,063      
Internet Consumer And Business Services | Rhino Labs Incorporation | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 470,000 [1],[31] $ 470,000 [2],[32]        
Investments at Fair Value $ 344,000 [31] $ 77,000 [32]        
Investment, Acquisition Date Mar. 12, 2021 [5] Mar. 12, 2021 [6]        
Shares | shares 13,106 [31] 13,106 [32] 13,106 [31] 13,106 [32]    
Internet Consumer And Business Services | Skyword, Inc. | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost $ 83,000 [1] $ 83,000 [2]        
Investments at Fair Value $ 2,000 $ 7,000        
Investment, Acquisition Date Aug. 23, 2019 [5] Aug. 23, 2019 [6]        
Shares | shares 444,444 444,444 444,444 444,444    
Internet Consumer And Business Services | Tectura Corporation | Equity            
Investment Holdings [Line Items]            
Investment cost $ 900,000 [1] $ 900,000 [2]        
Investments at Fair Value $ 0 $ 0        
Shares | shares 415,994,863 415,994,863 415,994,863 415,994,863    
Internet Consumer And Business Services | Tectura Corporation | Equity | Preferred Series BB            
Investment Holdings [Line Items]            
Investment cost $ 0 [1],[24] $ 0 [2],[25]        
Investments at Fair Value $ 0 [24] $ 0 [25]        
Investment, Acquisition Date Jun. 06, 2016 [5] Jun. 06, 2016 [6],[25]        
Shares | shares 1,000,000 [24] 1,000,000 [25] 1,000,000 [24] 1,000,000 [25]    
Internet Consumer And Business Services | Tectura Corporation | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 900,000 [1],[24] $ 900,000 [2],[25]        
Investments at Fair Value $ 0 [24] $ 0 [25]        
Investment, Acquisition Date May 23, 2018 [5] May 23, 2018 [6],[25]        
Shares | shares 414,994,863 [24] 414,994,863 [25] 414,994,863 [24] 414,994,863 [25]    
Internet Consumer And Business Services | Tectura Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Principal Amount $ 31,953,000 $ 31,953,000        
Investment cost 21,513,000 [1] 21,513,000 [2]        
Investments at Fair Value 8,318,000 8,269,000        
Internet Consumer And Business Services | Thumbtack, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost 844,000 [1] 552,000 [2]        
Investments at Fair Value $ 459,000 $ 786,000        
Investment, Acquisition Date May 01, 2018 [5] May 01, 2018 [6]        
Shares | shares 267,225 190,953 267,225 190,953    
Internet Consumer And Business Services | Veem, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 126,000          
Investments at Fair Value $ 48,000          
Investment, Acquisition Date [5] Mar. 31, 2022          
Shares | shares 98,428   98,428      
Internet Consumer And Business Services | Veem, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Principal Amount $ 10,041,000          
Investments at Fair Value 10,022,000          
Internet Consumer And Business Services | Worldremit Group Limited | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost [1] 155,000          
Investments at Fair Value $ 405,000          
Shares | shares 79,083   79,083      
Internet Consumer And Business Services | Worldremit Group Limited | Warrant Investment | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost [1],[19],[29],[30] $ 129,000          
Investments at Fair Value [19],[29],[30] $ 399,000          
Investment, Acquisition Date [5] Feb. 11, 2021          
Shares | shares [19],[29],[30] 77,215   77,215      
Internet Consumer And Business Services | Worldremit Group Limited | Warrant Investment | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost [1],[19],[29],[30] $ 26,000          
Investments at Fair Value [19],[29],[30] $ 6,000          
Investment, Acquisition Date [5] Aug. 27, 2021          
Shares | shares [19],[29],[30] 1,868   1,868      
Internet Consumer And Business Services | Houzz, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 20,000 [1] $ 20,000 [2]        
Investments at Fair Value $ 1,000 $ 116,000        
Investment, Acquisition Date Oct. 29, 2019 [5] Oct. 29, 2019 [6]        
Shares | shares 529,661 529,661 529,661 529,661    
Internet Consumer And Business Services | Black Crow AI, Inc. affiliates | Equity | Preferred Series Seed            
Investment Holdings [Line Items]            
Investment cost [2],[35]   $ 1,000,000        
Investments at Fair Value [35]   $ 1,120,000        
Investment, Acquisition Date [6],[35]   Mar. 24, 2021        
Shares | shares [35]   872,797   872,797    
Internet Consumer And Business Services | Black Crow AI, Inc. affiliates | Equity | Preferred Note            
Investment Holdings [Line Items]            
Investment cost $ 3,000,000 [1],[36] $ 3,000,000 [2]        
Investments at Fair Value $ 3,000,000 [36] $ 3,000,000        
Investment, Acquisition Date Mar. 24, 2021 [5] Mar. 24, 2021 [6]        
Shares | shares 3 [36] 3 3 [36] 3    
Internet Consumer And Business Services | Contentful Global, Inc. | Equity            
Investment Holdings [Line Items]            
Investment cost $ 638,000 [1] $ 638,000 [2]        
Investments at Fair Value $ 924,000 $ 1,894,000        
Shares | shares 149,500 149,500 149,500 149,500    
Internet Consumer And Business Services | Contentful Global, Inc. | Equity | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost $ 500,000 [1],[29],[30] $ 500,000 [2],[27],[28]        
Investments at Fair Value $ 685,000 [29],[30] $ 1,388,000 [27],[28]        
Investment, Acquisition Date Nov. 20, 2018 [5] Nov. 20, 2018 [6],[27],[28]        
Shares | shares 108,500 [29],[30] 108,500 [27],[28] 108,500 [29],[30] 108,500 [27],[28]    
Internet Consumer And Business Services | Contentful Global, Inc. | Equity | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 138,000 [1],[29],[30] $ 138,000 [2],[27],[28]        
Investments at Fair Value $ 239,000 [29],[30] $ 506,000 [27],[28]        
Investment, Acquisition Date Dec. 22, 2020 [5] Dec. 22, 2020 [6],[27],[28]        
Shares | shares 41,000 [29],[30] 41,000 [27],[28] 41,000 [29],[30] 41,000 [27],[28]    
Internet Consumer And Business Services | DoorDash, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 945,000 [1],[5] $ 945,000 [2],[6]        
Investments at Fair Value $ 4,055,000 [5] $ 12,209,000 [6]        
Investment, Acquisition Date Dec. 20, 2018 [5] Dec. 20, 2018 [6]        
Shares | shares 81,996 [5] 81,996 [6] 81,996 [5] 81,996 [6]    
Internet Consumer And Business Services | Lyft Inc | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 5,263,000 [1],[5] $ 5,263,000 [2],[6]        
Investments at Fair Value $ 1,327,000 [5] $ 4,305,000 [6]        
Investment, Acquisition Date Dec. 26, 2018 [5] Dec. 26, 2018 [6]        
Shares | shares 100,738 [5] 100,738 [6] 100,738 [5] 100,738 [6]    
Internet Consumer And Business Services | Nerdy Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,000,000 [1],[5],[22] $ 1,000,000 [2],[6]        
Investments at Fair Value $ 209,000 [5],[22] $ 450,000 [6]        
Investment, Acquisition Date Sep. 17, 2021 [5] Sep. 17, 2021 [6]        
Shares | shares 100,000 [5],[22] 100,000 [6] 100,000 [5],[22] 100,000 [6]    
Internet Consumer And Business Services | Nextdoor.com, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 4,854,000 [1],[5] $ 4,854,000 [2],[6],[34]        
Investments at Fair Value $ 2,844,000 [5] $ 6,624,000 [6],[34]        
Investment, Acquisition Date Aug. 01, 2018 [5] Aug. 01, 2018 [6]        
Shares | shares 1,019,255 [5] 1,019,255 [6],[34] 1,019,255 [5] 1,019,255 [6],[34]    
Internet Consumer And Business Services | OfferUp, Inc. | Equity            
Investment Holdings [Line Items]            
Investment cost $ 2,295,000 [1] $ 2,295,000 [2]        
Investments at Fair Value $ 577,000 $ 2,471,000        
Shares | shares 394,790 394,790 394,790 394,790    
Internet Consumer And Business Services | OfferUp, Inc. | Equity | Preferred Series A            
Investment Holdings [Line Items]            
Investment cost $ 1,663,000 [1] $ 1,663,000 [2]        
Investments at Fair Value $ 418,000 $ 1,791,000        
Investment, Acquisition Date Oct. 25, 2016 [5] Oct. 25, 2016 [6]        
Shares | shares 286,080 286,080 286,080 286,080    
Internet Consumer And Business Services | OfferUp, Inc. | Equity | Preferred Series A-1            
Investment Holdings [Line Items]            
Investment cost $ 632,000 [1] $ 632,000 [2]        
Investments at Fair Value $ 159,000 $ 680,000        
Investment, Acquisition Date Oct. 25, 2016 [5] Oct. 25, 2016 [6]        
Shares | shares 108,710 108,710 108,710 108,710    
Internet Consumer And Business Services | Oportun | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 577,000 [1],[5] $ 577,000 [2],[6]        
Investments at Fair Value $ 211,000 [5] $ 980,000 [6]        
Investment, Acquisition Date Jun. 28, 2013 [5] Jun. 28, 2013 [6]        
Shares | shares 48,365 [5] 48,365 [6] 48,365 [5] 48,365 [6]    
Internet Consumer And Business Services | Reischling Press, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 15,000 [1] $ 15,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Jul. 31, 2020 [5] Jul. 31, 2020 [6]        
Shares | shares 1,163 1,163 1,163 1,163    
Internet Consumer And Business Services | Savage X Holding, LLC | Equity | Class A Units            
Investment Holdings [Line Items]            
Investment cost $ 13,000 [1] $ 13,000 [2]        
Investments at Fair Value $ 179,000 $ 71,000        
Investment, Acquisition Date Apr. 30, 2010 [5] Apr. 30, 2010 [6]        
Shares | shares 42,137 42,137 42,137 42,137    
Internet Consumer And Business Services | Savage X Holding, LLC | Warrant Investment | Class A Units            
Investment Holdings [Line Items]            
Investment cost [1] $ 0          
Investments at Fair Value $ 875,000          
Investment, Acquisition Date [5] Jun. 27, 2014          
Shares | shares 206,185   206,185      
Internet Consumer And Business Services | TFG Holding, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 89,000 [1] $ 89,000 [2]        
Investments at Fair Value $ 95,000 $ 216,000        
Investment, Acquisition Date Apr. 30, 2010 [5] Apr. 30, 2010 [6]        
Shares | shares 42,989 42,989 42,989 42,989    
Internet Consumer And Business Services | TFG Holding, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 0          
Investments at Fair Value $ 17,000          
Investment, Acquisition Date [5] Jun. 27, 2014          
Shares | shares 206,185   206,185      
Internet Consumer And Business Services | Uber Technologies, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 318,000 [1],[5] $ 318,000 [2],[6]        
Investments at Fair Value $ 874,000 [5] $ 1,383,000 [6]        
Investment, Acquisition Date Dec. 01, 2020 [5] Dec. 01, 2020 [6]        
Shares | shares 32,991 [5] 32,991 [6] 32,991 [5] 32,991 [6]    
Internet Consumer And Business Services | Snagajobcom Inc | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost $ 860,000 [1] $ 860,000 [2]        
Investments at Fair Value $ 258,000 $ 382,000        
Shares | shares 3,611,537 3,611,537 3,611,537 3,611,537    
Internet Consumer And Business Services | Snagajobcom Inc | Warrant Investment | Preferred Series A            
Investment Holdings [Line Items]            
Investment cost $ 782,000 [1],[18] $ 782,000 [2],[33]        
Investments at Fair Value $ 120,000 [18] $ 171,000 [33]        
Investment, Acquisition Date Jun. 30, 2016 [5] Jun. 30, 2016 [6]        
Shares | shares 1,800,000 [18] 1,800,000 [33] 1,800,000 [18] 1,800,000 [33]    
Internet Consumer And Business Services | Snagajobcom Inc | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost $ 62,000 [1],[18] $ 62,000 [2],[33]        
Investments at Fair Value $ 69,000 [18] $ 90,000 [33]        
Investment, Acquisition Date Aug. 01, 2018 [5] Aug. 01, 2018 [6]        
Shares | shares 1,211,537 [18] 1,211,537 [33] 1,211,537 [18] 1,211,537 [33]    
Internet Consumer And Business Services | Snagajobcom Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 16,000 [1],[18] $ 16,000 [2],[33]        
Investments at Fair Value $ 69,000 [18] $ 121,000 [33]        
Investment, Acquisition Date Apr. 20, 2020 [5] Apr. 20, 2020 [6]        
Shares | shares 600,000 [18] 600,000 [33] 600,000 [18] 600,000 [33]    
Internet Consumer And Business Services | Aria Systems, Inc. | Warrant Investment | Preferred Series G            
Investment Holdings [Line Items]            
Investment cost $ 74,000 [1] $ 74,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date May 22, 2015 [5] May 22, 2015 [6]        
Shares | shares 231,535 231,535 231,535 231,535    
Internet Consumer And Business Services | Cloudpay, Inc. | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost $ 54,000 [1],[29],[30] $ 54,000 [2],[27],[28]        
Investments at Fair Value $ 310,000 [29],[30] $ 348,000 [27],[28]        
Investment, Acquisition Date Apr. 10, 2018 [5] Apr. 10, 2018 [6],[27],[28]        
Shares | shares 6,763 [29],[30] 6,763 [27],[28] 6,763 [29],[30] 6,763 [27],[28]    
Internet Consumer And Business Services | First Insight, Inc. | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost $ 95,000 [1] $ 96,000 [2]        
Investments at Fair Value $ 35,000 $ 105,000        
Investment, Acquisition Date May 10, 2018 [5] May 10, 2018 [6]        
Shares | shares 75,917 75,917 75,917 75,917    
Internet Consumer And Business Services | Landing Holdings Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 116,000 [1],[31] $ 116,000 [2],[32]        
Investments at Fair Value $ 117,000 [31] $ 141,000 [32]        
Investment, Acquisition Date Mar. 12, 2021 [5] Mar. 12, 2021 [6]        
Shares | shares 11,806 [31] 11,806 [32] 11,806 [31] 11,806 [32]    
Internet Consumer And Business Services | Lendio, Inc. | Warrant Investment | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost $ 39,000 [1] $ 39,000 [2]        
Investments at Fair Value $ 35,000 $ 84,000        
Investment, Acquisition Date Mar. 29, 2019 [5] Mar. 29, 2019 [6]        
Shares | shares 127,032 127,032 127,032 127,032    
Internet Consumer And Business Services | RumbleON, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 88,000 [1],[5] $ 88,000 [2],[6]        
Investments at Fair Value $ 1,000 [5] $ 33,000 [6]        
Investment, Acquisition Date Apr. 30, 2018 [5] Apr. 30, 2018 [6]        
Shares | shares 5,139 [5] 5,139 [6] 5,139 [5] 5,139 [6]    
Internet Consumer And Business Services | ShareThis, Inc. | Warrant Investment | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 547,000 [1] $ 547,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Dec. 14, 2012 [5] Dec. 14, 2012 [6]        
Shares | shares 493,502 493,502 493,502 493,502    
Internet Consumer And Business Services | The Faction Group LLC | Warrant Investment | Preferred Series AA            
Investment Holdings [Line Items]            
Investment cost $ 234,000 [1],[7] $ 234,000 [2]        
Investments at Fair Value $ 387,000 $ 650,000        
Investment, Acquisition Date Nov. 03, 2014 [5] Nov. 03, 2014 [6]        
Shares | shares 8,076 8,076 8,076 8,076    
Internet Consumer And Business Services | Xometry, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2],[6]   $ 47,000        
Investments at Fair Value [6]   $ 3,038,000        
Investment, Acquisition Date [6]   May 09, 2018        
Shares | shares [6]   87,784   87,784    
Internet Consumer And Business Services | Interactions Corporation | Warrant Investment | Series G Three Preferred Stock            
Investment Holdings [Line Items]            
Investment cost [2]   $ 204,000        
Investments at Fair Value   $ 505,000        
Investment, Acquisition Date [6]   Jun. 16, 2015        
Shares | shares   68,187   68,187    
Internet Consumer And Business Services | Brigade Group, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2]   $ 93,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Mar. 01, 2013        
Shares | shares   9,023   9,023    
Internet Consumer And Business Services | Logic Source | Warrant Investment | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost [2]   $ 30,000        
Investments at Fair Value   $ 210,000        
Investment, Acquisition Date [6]   Mar. 21, 2016        
Shares | shares   79,625   79,625    
Internet Consumer And Business Services | Tapjoy, Inc. | Warrant Investment | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost [2]   $ 317,000        
Investments at Fair Value   $ 443,000        
Investment, Acquisition Date [6]   Jul. 01, 2014        
Shares | shares   748,670   748,670    
Internet Consumer And Business Services | Zepz (p.k.a. Worldremit Group Limited) | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost [2]   $ 155,000        
Investments at Fair Value   $ 1,987,000        
Shares | shares   79,083   79,083    
Internet Consumer And Business Services | Zepz (p.k.a. Worldremit Group Limited) | Warrant Investment | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost [2],[21],[27],[28]   $ 129,000        
Investments at Fair Value [21],[27],[28]   $ 1,962,000        
Investment, Acquisition Date [6],[27],[28]   Feb. 11, 2021        
Shares | shares [21],[27],[28]   77,215   77,215    
Internet Consumer And Business Services | Zepz (p.k.a. Worldremit Group Limited) | Warrant Investment | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost [2],[21],[27],[28]   $ 26,000        
Investments at Fair Value [21],[27],[28]   $ 25,000        
Investment, Acquisition Date [6],[27],[28]   Aug. 27, 2021        
Shares | shares [21],[27],[28]   1,868   1,868    
Internet Consumer And Business Services | Senior Secured | Salary.com, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-09   2027-09      
Investment, Basis Spread, Variable Rate [7] 8.00%   8.00%      
Investment, Interest Rate, Floor [7] 9.00%   9.00%      
Investment cost [1],[13] $ 17,640,000          
Investments at Fair Value [13] $ 17,640,000          
Internet Consumer And Business Services | Senior Secured | SeatGeek, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date 2023-06   2023-06      
Investment, Basis Spread, Variable Rate [7] 5.00%   5.00%      
Investment, Interest Rate, Floor [7] 10.50%   10.50%      
Investment, Interest Rate, Paid in Kind [7] 0.50%   0.50%      
Principal Amount [9],[12],[17],[18],[19] $ 60,838,000          
Investment cost [1],[9],[12],[17],[18],[19] 60,529,000          
Investments at Fair Value [9],[12],[17],[18],[19] $ 60,529,000          
Internet Consumer And Business Services | Senior Secured | SeatGeek, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-05 2023-06 2026-05 2023-06    
Investment, Basis Spread, Variable Rate 7.00% [7] 5.00% [11] 7.00% [7] 5.00% [11]    
Investment, Interest Rate, Floor 10.50% [7] 10.50% [11] 10.50% [7] 10.50% [11]    
Investment, Interest Rate, Paid in Kind 0.50% [7] 0.50% [11] 0.50% [7] 0.50% [11]    
Principal Amount $ 25,040,000 [9],[12],[17],[18],[19] $ 60,607,000 [20]        
Investment cost 24,869,000 [1],[9],[12],[17],[18],[19] 59,983,000 [2],[20]        
Investments at Fair Value $ 25,591,000 [9],[12],[17],[18],[19] $ 60,316,000 [20]        
Internet Consumer And Business Services | Senior Secured | App Direct Incorporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-04 2024-08 2026-04 2024-08    
Investment Interest Rate [11]   7.95%   7.95%    
Investment, Basis Spread, Variable Rate 5.50% [7] 5.90% [11] 5.50% [7] 5.90% [11]    
Investment, Interest Rate, Floor 8.75% [7] 9.15% [11] 8.75% [7] 9.15% [11]    
Interest Rate and Floor [11]   7.95%   7.95%    
Principal Amount $ 30,790,000 [10],[18] $ 30,790,000        
Investment cost 31,733,000 [1],[10],[18] 31,416,000 [2]        
Investments at Fair Value $ 31,991,000 [10],[18] $ 32,248,000        
Internet Consumer And Business Services | Senior Secured | Carwow LTD | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-12 2024-12 2024-12 2024-12    
Investment Interest Rate [11],[27],[28]   4.95%   4.95%    
Investment, Basis Spread, Variable Rate 4.70% [7] 4.70% [11],[27],[28] 4.70% [7] 4.70% [11],[27],[28]    
Investment, Interest Rate, Floor 7.95% [7] 7.95% [11],[27],[28] 7.95% [7] 7.95% [11],[27],[28]    
Investment, Interest Rate, Paid in Kind 1.45% [7] 1.45% [11],[27],[28] 1.45% [7] 1.45% [11],[27],[28]    
Interest Rate and Floor [11],[27],[28]   4.95%   4.95%    
Principal Amount $ 21,021,000 [9],[29],[30]   £ 18,798 [9],[29],[30] £ 21,250 [20],[27],[28]    
Investment cost $ 25,845,000 [1],[9],[29],[30] $ 28,632,000 [2],[20],[27],[28]        
Investments at Fair Value [20],[27],[28]   $ 28,632,000        
Internet Consumer And Business Services | Senior Secured | Convoy, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-03   2026-03      
Investment, Basis Spread, Variable Rate [7] 3.20%   3.20%      
Investment, Interest Rate, Floor [7] 6.45%   6.45%      
Investment, Interest Rate, Paid in Kind [7] 1.95%   1.95%      
Principal Amount [8],[9],[19] $ 73,623,000          
Investment cost [1],[8],[9],[19] 72,447,000          
Investments at Fair Value [8],[9],[19] $ 73,092,000          
Internet Consumer And Business Services | Senior Secured | Jobandtalent USA, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-02   2025-02      
Investment, Basis Spread, Variable Rate [7] 8.86%   8.86%      
Investment, Interest Rate, Floor [7] 9.75%   9.75%      
Principal Amount [29],[30] $ 14,000,000          
Investment cost [1],[29],[30] 13,802,000          
Investments at Fair Value [29],[30] $ 13,865,000          
Internet Consumer And Business Services | Senior Secured | Nextroll, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date 2023-07 2022-06 2023-07 2022-06    
Investment Interest Rate [11]   3.50%   3.50%    
Investment, Basis Spread, Variable Rate [11]   3.75%   3.75%    
Investment, Interest Rate, Floor [11]   7.00%   7.00%    
Investment, Interest Rate, Paid in Kind [11]   2.95%   2.95%    
Interest Rate and Floor [11]   3.50%   3.50%    
Principal Amount $ 22,046,000 [9],[18] $ 21,555,000 [20],[23],[33]        
Investment cost 21,952,000 [1],[9],[18] 22,164,000 [2],[20],[23],[33]        
Investments at Fair Value $ 21,952,000 [9],[18] $ 22,164,000 [20],[23],[33]        
Internet Consumer And Business Services | Senior Secured | Nextroll, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 7.75%   7.75%      
Investment, Basis Spread, Variable Rate [7] 3.75%   3.75%      
Investment, Interest Rate, Paid in Kind [7] 2.95%   2.95%      
Interest Rate and Floor [7] 7.75%   7.75%      
Internet Consumer And Business Services | Senior Secured | Rhino Labs Incorporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-03 2024-03 2024-03 2024-03    
Investment, Basis Spread, Variable Rate 5.50% [7] 5.50% [11] 5.50% [7] 5.50% [11]    
Investment, Interest Rate, Floor 8.75% [7] 8.75% [11] 8.75% [7] 8.75% [11]    
Investment, Interest Rate, Paid in Kind 2.25% [7] 2.25% [11] 2.25% [7] 2.25% [11]    
Principal Amount $ 16,407,000 [9],[31] $ 16,136,000 [20],[32]        
Investment cost 16,180,000 [1],[9],[31] 15,765,000 [2],[20],[32]        
Investments at Fair Value $ 16,331,000 [9],[31] $ 15,876,000 [20],[32]        
Internet Consumer And Business Services | Senior Secured | R V Share Limited Liability Company | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-12 2026-12 2026-12 2026-12    
Investment, Basis Spread, Variable Rate 5.50% [7] 5.50% [11] 5.50% [7] 5.50% [11]    
Investment, Interest Rate, Floor 6.50% [7] 6.50% [11] 6.50% [7] 6.50% [11]    
Investment, Interest Rate, Paid in Kind 4.00% [7] 4.00% [11] 4.00% [7] 4.00% [11]    
Principal Amount $ 20,489,000 [9],[10],[17],[31] $ 15,000,000 [15],[32]        
Investment cost 20,138,000 [1],[9],[10],[17],[31] 14,701,000 [2],[15],[32]        
Investments at Fair Value $ 20,130,000 [9],[10],[17],[31] $ 14,701,000 [15],[32]        
Internet Consumer And Business Services | Senior Secured | Skyword, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-09 2024-09 2024-09 2024-09    
Investment Interest Rate [11]   4.00%   4.00%    
Investment, Basis Spread, Variable Rate 3.88% [7] 3.88% [11] 3.88% [7] 3.88% [11]    
Investment, Interest Rate, Floor 9.38% [7] 9.38% [11] 9.38% [7] 9.38% [11]    
Investment, Interest Rate, Paid in Kind 1.90% [7] 1.90% [11] 1.90% [7] 1.90% [11]    
Interest Rate and Floor [11]   4.00%   4.00%    
Principal Amount $ 12,607,000 [9],[17] $ 12,426,000 [20]        
Investment cost 12,922,000 [1],[9],[17] 12,665,000 [2],[20]        
Investments at Fair Value $ 12,708,000 [9],[17] $ 12,521,000 [20]        
Internet Consumer And Business Services | Senior Secured | Thumbtack, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-04 2023-09 2026-04 2023-09    
Investment Interest Rate [11]   3.95%   3.95%    
Investment, Basis Spread, Variable Rate 4.95% [7] 3.45% [11] 4.95% [7] 3.45% [11]    
Investment, Interest Rate, Floor 8.95% [7] 8.95% [11] 8.95% [7] 8.95% [11]    
Investment, Interest Rate, Paid in Kind 1.50% [7] 1.50% [11] 1.50% [7] 1.50% [11]    
Interest Rate and Floor [11]   3.95%   3.95%    
Principal Amount $ 10,065,000 [9],[10],[18] $ 25,618,000 [20],[33]        
Investment cost 9,985,000 [1],[9],[10],[18] 25,965,000 [2],[20],[33]        
Investments at Fair Value 9,938,000 [9],[10],[18] $ 26,372,000 [20],[33]        
Internet Consumer And Business Services | Senior Secured | Veem, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost [1] $ 9,891,000          
Internet Consumer And Business Services | Senior Secured | Worldremit Group Limited | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-02 2025-02 2025-02 2025-02    
Investment Interest Rate [11],[27],[28]   3.00%   3.00%    
Investment, Basis Spread, Variable Rate 9.25% [7] 9.25% [11],[27],[28] 9.25% [7] 9.25% [11],[27],[28]    
Investment, Interest Rate, Floor 10.25% [7] 10.25% [11],[27],[28] 10.25% [7] 10.25% [11],[27],[28]    
Interest Rate and Floor [11],[27],[28]   3.00%   3.00%    
Principal Amount $ 94,500,000 [8],[12],[18],[19],[29],[30] $ 103,000,000 [21],[23],[27],[28],[33]        
Investment cost 94,115,000 [1],[8],[12],[18],[19],[29],[30] 101,674,000 [2],[21],[23],[27],[28],[33]        
Investments at Fair Value $ 92,293,000 [8],[12],[18],[19],[29],[30] $ 100,472,000 [21],[23],[27],[28],[33]        
Internet Consumer And Business Services | Senior Secured | E Pay Policy Holdings L L C | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2024-12   2024-12    
Investment, Basis Spread, Variable Rate [11]   8.50%   8.50%    
Investment, Interest Rate, Floor [11]   9.50%   9.50%    
Principal Amount [14],[15]   $ 8,169,000        
Investment cost [2],[14],[15]   8,011,000        
Investments at Fair Value [14],[15]   $ 7,967,000        
Internet Consumer And Business Services | Senior Secured | Logic Source | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-07   2027-07      
Investment, Basis Spread, Variable Rate [7] 8.93%   8.93%      
Investment, Interest Rate, Floor [7] 9.93%   9.93%      
Principal Amount [10] $ 13,300,000          
Investment cost [1],[10] 13,017,000          
Investments at Fair Value [10] $ 13,017,000          
Internet Consumer And Business Services | Senior Secured | Exit Fee | App Direct Incorporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 9.70%   9.70%      
Interest Rate and Floor [7] 9.70%   9.70%      
Internet Consumer And Business Services | Senior Secured | Exit Fee | Carwow LTD | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.95%   4.95%      
Interest Rate and Floor [7] 4.95%   4.95%      
Internet Consumer And Business Services | Senior Secured | Exit Fee | Convoy, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.55%   4.55%      
Interest Rate and Floor [7] 4.55%   4.55%      
Internet Consumer And Business Services | Senior Secured | Exit Fee | Jobandtalent USA, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.00%   3.00%      
Interest Rate and Floor [7] 3.00%   3.00%      
Internet Consumer And Business Services | Senior Secured | Exit Fee | Nextroll, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 1.95%   1.95%      
Interest Rate and Floor [7] 1.95%   1.95%      
Internet Consumer And Business Services | Senior Secured | Exit Fee | Skyword, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.00%   4.00%      
Interest Rate and Floor [7] 4.00%   4.00%      
Internet Consumer And Business Services | Senior Secured | Exit Fee | Thumbtack, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.95%   3.95%      
Interest Rate and Floor [7] 3.95%   3.95%      
Internet Consumer And Business Services | Senior Secured | Exit Fee | Worldremit Group Limited | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.00%   3.00%      
Interest Rate and Floor [7] 3.00%   3.00%      
Internet Consumer And Business Services | Senior Secured Tranche A [Member] | Tectura Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-07 2024-07 2024-07 2024-07    
Investment, Interest Rate, Paid in Kind 5.00% [7] 5.00% [11],[25],[37] 5.00% [7] 5.00% [11],[25],[37]    
Principal Amount $ 10,680,000 [9],[24],[38] $ 10,680,000 [20],[25],[37]        
Investment cost 240,000 [1],[9],[24],[38] 240,000 [2],[20],[25],[37]        
Investments at Fair Value $ 0 [9],[24],[38] $ 0 [20],[25],[37]        
Internet Consumer And Business Services | Senior Secured Tranche A [Member] | Veem, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-03   2025-03      
Investment, Basis Spread, Variable Rate [7] 4.00%   4.00%      
Investment, Interest Rate, Floor [7] 7.25%   7.25%      
Investment, Interest Rate, Paid in Kind [7] 1.25%   1.25%      
Principal Amount [9],[17] $ 5,027,000          
Investment cost [1],[9],[17] 4,959,000          
Investments at Fair Value [9],[17] $ 4,967,000          
Internet Consumer And Business Services | Senior Secured Tranche A [Member] | Exit Fee | Veem, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.50%   4.50%      
Interest Rate and Floor [7] 4.50%   4.50%      
Internet Consumer And Business Services | Senior Secured Tranche B [Member] | Tectura Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-07 2024-07 2024-07 2024-07    
Investment, Interest Rate, Paid in Cash 8.25% [7] 8.25% [11],[25],[37] 8.25% [7] 8.25% [11],[25],[37]    
Principal Amount $ 8,250,000 [24] $ 8,250,000 [25],[37]        
Investment cost 8,250,000 [1],[24] 8,250,000 [2],[25],[37]        
Investments at Fair Value $ 8,250,000 [24] $ 8,250,000 [25],[37]        
Internet Consumer And Business Services | Senior Secured Tranche B [Member] | Veem, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-03   2025-03      
Investment, Basis Spread, Variable Rate [7] 4.70%   4.70%      
Investment, Interest Rate, Floor [7] 7.95%   7.95%      
Investment, Interest Rate, Paid in Kind [7] 1.50%   1.50%      
Principal Amount $ 5,014,000          
Investment cost [1] 4,932,000          
Investments at Fair Value $ 5,055,000          
Internet Consumer And Business Services | Senior Secured Tranche B [Member] | Exit Fee | Veem, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.50%   4.50%      
Interest Rate and Floor [7] 4.50%   4.50%      
Internet Consumer And Business Services | Senior Secured Tranche C [Member] | Tectura Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-07 2024-07 2024-07 2024-07    
Investment, Interest Rate, Paid in Kind 5.00% [7] 5.00% [11],[25],[37] 5.00% [7] 5.00% [11],[25],[37]    
Principal Amount $ 13,023,000 [9],[24],[38] $ 13,023,000 [20],[25],[37]        
Investment cost 13,023,000 [1],[9],[24],[38] 13,023,000 [2],[20],[25],[37]        
Investments at Fair Value 68,000 [9],[24],[38] 19,000 [20],[25],[37]        
Internet Consumer And Business Services | Debt Investments            
Investment Holdings [Line Items]            
Investment cost 487,830,000 [1] 363,165,000 [2]        
Investments at Fair Value 468,792,000 $ 349,963,000        
Internet Consumer And Business Services | Convertible Debt | Salary.com, LLC | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Investments at Fair Value [13] $ 18,000          
Internet Consumer And Business Services | Convertible Debt | Houzz, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2028-05   2028-05    
Investment, Interest Rate, Paid in Kind [11],[26]   5.50%   5.50%    
Principal Amount [20],[26]   $ 20,676,000        
Investment cost [2],[20],[26]   20,676,000        
Investments at Fair Value [20],[26]   20,425,000        
Internet Consumer And Business Services | Convertible Debt | Houzz, Inc. | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2028-05   2028-05      
Investment, Interest Rate, Paid in Kind [7] 5.50%   5.50%      
Principal Amount [9],[39] $ 21,252,000          
Investment cost [1],[9],[39] 21,252,000          
Investments at Fair Value [9],[39] 20,354,000          
Manufacturing Technology | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost [1] 726,000          
Investments at Fair Value 4,338,000          
Manufacturing Technology | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment cost 15,902,000 [1] 14,995,000 [2]        
Investments at Fair Value 16,045,000 $ 14,995,000        
Manufacturing Technology | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost [1] 23,597,000          
Investments at Fair Value 23,509,000          
Manufacturing Technology | Bright Machines, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] 151,000          
Investments at Fair Value $ 320,000          
Investment, Acquisition Date [5] Mar. 31, 2022          
Shares | shares 196,335   196,335      
Manufacturing Technology | MacroFab, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 528,000          
Investments at Fair Value $ 603,000          
Investment, Acquisition Date [5] Mar. 23, 2022          
Shares | shares 1,111,111   1,111,111      
Manufacturing Technology | Xometry, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5] $ 47,000          
Investments at Fair Value [5] $ 3,415,000          
Investment, Acquisition Date [5] May 09, 2018          
Shares | shares [5] 87,784   87,784      
Manufacturing Technology | Senior Secured | Bright Machines, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date 2022-11 2022-11 2022-11 2022-11    
Investment Interest Rate [11]   6.95%   6.95%    
Investment, Basis Spread, Variable Rate 5.70% [7] 5.70% [11] 5.70% [7] 5.70% [11]    
Investment, Interest Rate, Floor 8.95% [7] 8.95% [11] 8.95% [7] 8.95% [11]    
Interest Rate and Floor [11]   6.95%   6.95%    
Principal Amount $ 15,000,000 [8],[12] $ 15,000,000 [23]        
Investment cost 15,902,000 [1],[8],[12] 14,995,000 [2],[23]        
Investments at Fair Value $ 16,045,000 [8],[12] 14,995,000 [23]        
Manufacturing Technology | Senior Secured | MacroFab, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-03   2026-03      
Investment Interest Rate [7] 7.60%   7.60%      
Investment, Basis Spread, Variable Rate [7] 4.35%   4.35%      
Investment, Interest Rate, Paid in Kind [7] 1.25%   1.25%      
Interest Rate and Floor [7] 7.60%   7.60%      
Principal Amount [9],[18] $ 17,083,000          
Investment cost [1],[9],[18] 16,616,000          
Investments at Fair Value [9],[18] $ 16,469,000          
Manufacturing Technology | Senior Secured | Ouster, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-05   2026-05      
Investment, Basis Spread, Variable Rate [7] 6.15%   6.15%      
Investment, Interest Rate, Floor [7] 9.40%   9.40%      
Principal Amount [10],[17],[29] $ 7,000,000          
Investment cost [1],[10],[17],[29] 6,981,000          
Investments at Fair Value [10],[17],[29] $ 7,040,000          
Manufacturing Technology | Senior Secured | Exit Fee | Bright Machines, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 6.95%   6.95%      
Interest Rate and Floor [7] 6.95%   6.95%      
Manufacturing Technology | Senior Secured | Exit Fee | MacroFab, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.50%   4.50%      
Interest Rate and Floor [7] 4.50%   4.50%      
Manufacturing Technology | Senior Secured | Exit Fee | Ouster, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 7.45%   7.45%      
Interest Rate and Floor [7] 7.45%   7.45%      
Manufacturing Technology | Debt Investments            
Investment Holdings [Line Items]            
Investment cost $ 39,499,000 [1] 14,995,000 [2]        
Investments at Fair Value 39,554,000 14,995,000        
Medical Devices & Equipment            
Investment Holdings [Line Items]            
Investments at Fair Value 17,421,000 12,612,000        
Medical Devices & Equipment | Equity            
Investment Holdings [Line Items]            
Investment cost 2,953,000 [1] 3,991,000 [2]        
Investments at Fair Value 2,143,000 10,538,000        
Medical Devices & Equipment | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 2,035,000 [1] 2,483,000 [2]        
Investments at Fair Value 443,000 2,074,000        
Medical Devices & Equipment | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost [1] 14,927,000          
Investments at Fair Value 14,835,000          
Medical Devices & Equipment | Lucira Health, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5] 110,000          
Investments at Fair Value [5] $ 0          
Investment, Acquisition Date [5] Feb. 04, 2022          
Shares | shares [5] 59,642   59,642      
Medical Devices & Equipment | Coronado Aesthetics, LLC | Equity            
Investment Holdings [Line Items]            
Investment cost $ 250,000 [1] 250,000 [2]        
Investments at Fair Value $ 400,000 $ 565,000        
Shares | shares 5,180,000 5,180,000 5,180,000 5,180,000    
Medical Devices & Equipment | Coronado Aesthetics, LLC | Equity | Preferred Series A-2            
Investment Holdings [Line Items]            
Investment cost $ 250,000 [1],[24] $ 250,000 [2],[25]        
Investments at Fair Value $ 391,000 [24] $ 500,000 [25]        
Investment, Acquisition Date Oct. 15, 2021 [5] Oct. 15, 2021 [6],[25]        
Shares | shares 5,000,000 [24] 5,000,000 [25] 5,000,000 [24] 5,000,000 [25]    
Medical Devices & Equipment | Coronado Aesthetics, LLC | Equity | Common Units            
Investment Holdings [Line Items]            
Investment cost $ 0 [1],[24] $ 0 [2],[25]        
Investments at Fair Value $ 9,000 [24] $ 65,000 [25]        
Investment, Acquisition Date Oct. 15, 2021 [5] Oct. 15, 2021 [6],[25]        
Shares | shares 180,000 [24] 180,000 [25] 180,000 [24] 180,000 [25]    
Medical Devices & Equipment | Flowonix Medical Incorporated | Equity | Preferred Series AA            
Investment Holdings [Line Items]            
Investment cost $ 1,500,000 [1] $ 1,500,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Nov. 03, 2014 [5] Nov. 03, 2014 [6]        
Shares | shares 221,893 221,893 221,893 221,893    
Medical Devices & Equipment | Flowonix Medical Incorporated | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost $ 714,000 [1] $ 714,000 [2]        
Investments at Fair Value $ 0 $ 0        
Shares | shares 836,752 881,131 836,752 881,131    
Medical Devices & Equipment | Flowonix Medical Incorporated | Warrant Investment | Preferred Series BB            
Investment Holdings [Line Items]            
Investment cost $ 352,000 [1] $ 351,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Sep. 21, 2018 [5] Sep. 21, 2018 [6]        
Shares | shares 725,806 725,806 725,806 725,806    
Medical Devices & Equipment | Flowonix Medical Incorporated | Warrant Investment | Preferred Series AA            
Investment Holdings [Line Items]            
Investment cost $ 362,000 [1],[18] $ 363,000 [2],[33]        
Investments at Fair Value $ 0 [18] $ 0 [33]        
Investment, Acquisition Date Nov. 03, 2014 [5] Nov. 03, 2014 [6]        
Shares | shares 110,946 [18] 155,325 [33] 110,946 [18] 155,325 [33]    
Medical Devices & Equipment | Gelesis, Inc. | Equity            
Investment Holdings [Line Items]            
Investment cost [2]   $ 1,003,000        
Investments at Fair Value   $ 9,772,000        
Shares | shares   662,071   662,071    
Medical Devices & Equipment | Gelesis, Inc. | Equity | Preferred Series A-1            
Investment Holdings [Line Items]            
Investment cost [2]   $ 503,000        
Investments at Fair Value   $ 3,593,000        
Investment, Acquisition Date [6]   Dec. 30, 2011        
Shares | shares   243,432   243,432    
Medical Devices & Equipment | Gelesis, Inc. | Equity | Preferred Series A-2            
Investment Holdings [Line Items]            
Investment cost [2]   $ 500,000        
Investments at Fair Value   $ 2,828,000        
Investment, Acquisition Date [6]   Dec. 31, 2011        
Shares | shares   191,626   191,626    
Medical Devices & Equipment | Gelesis, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 871,000 [1],[5] $ 0 [2]        
Investments at Fair Value $ 1,611,000 [5] $ 3,351,000        
Investment, Acquisition Date Nov. 30, 2009 [5] Nov. 30, 2009 [6]        
Shares | shares 1,490,700 [5] 227,013 1,490,700 [5] 227,013    
Medical Devices & Equipment | ViewRay, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 332,000 [1],[5] $ 333,000 [2],[6]        
Investments at Fair Value $ 132,000 [5] $ 201,000 [6]        
Investment, Acquisition Date Dec. 16, 2013 [5] Dec. 16, 2013 [6]        
Shares | shares 36,457 [5] 36,457 [6] 36,457 [5] 36,457 [6]    
Medical Devices & Equipment | Aspire Bariatrics, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 455,000 [1] $ 455,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Jan. 28, 2015 [5] Jan. 28, 2015 [6]        
Shares | shares 22,572 22,572 22,572 22,572    
Medical Devices & Equipment | Intuity Medical, Inc. | Warrant Investment | Preferred Series B-1            
Investment Holdings [Line Items]            
Investment cost $ 294,000 [1] $ 294,000 [2]        
Investments at Fair Value $ 30,000 $ 264,000        
Investment, Acquisition Date Dec. 29, 2017 [5] Dec. 29, 2017 [6]        
Shares | shares 3,076,323 3,076,323 3,076,323 3,076,323    
Medical Devices & Equipment | Outset Medical, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 401,000 [1],[5] $ 401,000 [2],[6]        
Investments at Fair Value $ 413,000 [5] $ 1,797,000 [6]        
Investment, Acquisition Date Sep. 27, 2013 [5] Sep. 27, 2013 [6]        
Shares | shares 62,794 [5] 62,794 [6] 62,794 [5] 62,794 [6]    
Medical Devices & Equipment | Tela Bio, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 61,000 [1],[5] $ 61,000 [2],[6]        
Investments at Fair Value $ 0 [5] $ 13,000 [6]        
Investment, Acquisition Date Mar. 31, 2017 [5] Mar. 31, 2017 [6]        
Shares | shares 15,712 [5] 15,712 [6] 15,712 [5] 15,712 [6]    
Medical Devices & Equipment | Medrobotics Corporation | Equity            
Investment Holdings [Line Items]            
Investment cost [2]   $ 905,000        
Investments at Fair Value   $ 0        
Shares | shares   374,703   374,703    
Medical Devices & Equipment | Medrobotics Corporation | Equity | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost [2]   $ 250,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Sep. 12, 2013        
Shares | shares   136,798   136,798    
Medical Devices & Equipment | Medrobotics Corporation | Equity | Preferred Series F            
Investment Holdings [Line Items]            
Investment cost [2]   $ 155,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Oct. 22, 2014        
Shares | shares   73,971   73,971    
Medical Devices & Equipment | Medrobotics Corporation | Equity | Preferred Series G            
Investment Holdings [Line Items]            
Investment cost [2]   $ 500,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Oct. 16, 2015        
Shares | shares   163,934   163,934    
Medical Devices & Equipment | Medrobotics Corporation | Warrant Investment | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost [2]   $ 370,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Mar. 13, 2013        
Shares | shares   455,539   455,539    
Medical Devices & Equipment | SonaCare Medical, LLC | Warrant Investment | Preferred Series A            
Investment Holdings [Line Items]            
Investment cost [2]   $ 188,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Sep. 28, 2012        
Shares | shares   6,464   6,464    
Medical Devices & Equipment | Senior Secured | Lucira Health, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-02   2026-02      
Investment, Basis Spread, Variable Rate [7] 5.50%   5.50%      
Investment, Interest Rate, Floor [7] 8.75%   8.75%      
Principal Amount [17] $ 15,000,000          
Investment cost [1],[17] 14,927,000          
Investments at Fair Value [17] $ 14,835,000          
Medical Devices & Equipment | Senior Secured | Exit Fee | Lucira Health, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.25%   5.25%      
Interest Rate and Floor [7] 5.25%   5.25%      
Medical Devices & Equipment | Debt Investments            
Investment Holdings [Line Items]            
Investment cost [1] $ 14,927,000          
Investments at Fair Value 14,835,000          
Semiconductors            
Investment Holdings [Line Items]            
Investments at Fair Value 20,621,000 $ 22,498,000        
Semiconductors | Equity            
Investment Holdings [Line Items]            
Investment cost 160,000 [1] 160,000 [2]        
Investments at Fair Value 259,000 725,000        
Semiconductors | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 850,000 [1] 850,000 [2]        
Investments at Fair Value 715,000 2,701,000        
Semiconductors | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 19,492,000 [1] 19,072,000 [2]        
Investments at Fair Value 19,647,000 19,072,000        
Semiconductors | Fungible, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost 751,000 [1],[31] 751,000 [2],[32]        
Investments at Fair Value $ 77,000 [31] $ 751,000 [32]        
Investment, Acquisition Date Dec. 16, 2021 [5] Dec. 16, 2021 [6]        
Shares | shares 800,000 [31] 800,000 [32] 800,000 [31] 800,000 [32]    
Semiconductors | Achronix Semiconductor Corporation | Equity | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 160,000 [1] $ 160,000 [2]        
Investments at Fair Value $ 259,000 $ 725,000        
Investment, Acquisition Date Jul. 01, 2011 [5] Jul. 01, 2011 [6]        
Shares | shares 277,995 277,995 277,995 277,995    
Semiconductors | Achronix Semiconductor Corporation | Warrant Investment | Preferred Series D-2            
Investment Holdings [Line Items]            
Investment cost $ 99,000 [1] $ 99,000 [2]        
Investments at Fair Value $ 638,000 $ 1,950,000        
Investment, Acquisition Date Jun. 26, 2015 [5] Jun. 26, 2015 [6]        
Shares | shares 750,000 750,000 750,000 750,000    
Semiconductors | Senior Secured | Fungible, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-12 2024-12 2024-12 2024-12    
Investment Interest Rate [11]   4.95%   4.95%    
Investment, Basis Spread, Variable Rate 5.00% [7] 5.00% [11] 5.00% [7] 5.00% [11]    
Investment, Interest Rate, Floor 8.25% [7] 8.25% [11] 8.25% [7] 8.25% [11]    
Interest Rate and Floor [11]   4.95%   4.95%    
Principal Amount $ 20,000,000 [8],[31] $ 20,000,000 [23],[32]        
Investment cost 19,492,000 [1],[8],[31] 19,072,000 [2],[23],[32]        
Investments at Fair Value $ 19,647,000 [8],[31] 19,072,000 [23],[32]        
Semiconductors | Senior Secured | Exit Fee | Fungible, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.95%   4.95%      
Interest Rate and Floor [7] 4.95%   4.95%      
Semiconductors | Debt Investments            
Investment Holdings [Line Items]            
Investment cost [2]   19,072,000        
Investments at Fair Value $ 19,647,000 19,072,000        
Software            
Investment Holdings [Line Items]            
Investments at Fair Value 680,216,000 585,622,000        
Software | Equity            
Investment Holdings [Line Items]            
Investment cost 24,006,000 [1] 23,905,000 [2]        
Investments at Fair Value 24,997,000 45,087,000        
Software | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 7,639,000 [1] 5,594,000 [2]        
Investments at Fair Value 6,217,000 11,133,000        
Software | Investment Funds & Vehicles [Member]            
Investment Holdings [Line Items]            
Investment cost [1] 381,000          
Investments at Fair Value 381,000          
Software | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment cost 10,691,000 [1] 68,743,000 [2]        
Investments at Fair Value 10,691,000 68,287,000        
Software | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 614,819,000 [1] 437,659,000 [2]        
Investments at Fair Value 615,863,000 441,115,000        
Software | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 22,066,000 [1] 19,851,000 [2]        
Investments at Fair Value 22,066,000 20,000,000        
Software | Automation Anywhere, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] 448,000          
Investments at Fair Value $ 437,000          
Investment, Acquisition Date [5] Sep. 23, 2022          
Shares | shares 254,778   254,778      
Software | Cutover, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[29],[30] $ 26,000          
Investments at Fair Value [29],[30] $ 25,000          
Investment, Acquisition Date [5] Sep. 21, 2022          
Shares | shares [29],[30] 102,898   102,898      
Software | Liberty Zim Co-Invest L.P. | Investment Funds & Vehicles [Member]            
Investment Holdings [Line Items]            
Investment cost [1],[29],[30] $ 381,000          
Investments at Fair Value [29],[30] $ 381,000          
Investment, Acquisition Date [5] Jul. 21, 2022          
Software | Delphix Corp. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,594,000 [1] 1,594,000 [2],[21]        
Investments at Fair Value $ 2,306,000 $ 3,275,000 [21]        
Investment, Acquisition Date Oct. 08, 2019 [5] Oct. 08, 2019 [6]        
Shares | shares 718,898 718,898 [21] 718,898 718,898 [21]    
Software | Pymetrics, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2]   $ 77,000        
Investments at Fair Value   $ 218,000        
Investment, Acquisition Date [6]   Sep. 15, 2020        
Shares | shares   150,943   150,943    
Software | 3GTMS, LLC | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 1,000,000 [1] $ 1,000,000 [2]        
Investments at Fair Value $ 675,000 $ 985,000        
Investment, Acquisition Date Aug. 09, 2021 [5] Aug. 09, 2021 [6]        
Shares | shares 1,000,000 1,000,000 1,000,000 1,000,000    
Software | Brain Corporation | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 165,000 [1],[31] $ 165,000 [2],[32]        
Investments at Fair Value $ 61,000 [31] $ 132,000 [32]        
Investment, Acquisition Date Oct. 04, 2021 [5] Oct. 04, 2021 [6]        
Shares | shares 194,629 [31] 194,629 [32] 194,629 [31] 194,629 [32]    
Software | CloudBolt Software, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 117,000 [1] $ 117,000 [2]        
Investments at Fair Value $ 2,000 $ 85,000        
Investment, Acquisition Date Sep. 30, 2020 [5] Sep. 30, 2020 [6]        
Shares | shares 211,342 211,342 211,342 211,342    
Software | Dashlane, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 353,000 [1] $ 404,000 [2]        
Investments at Fair Value $ 120,000 $ 415,000        
Investment, Acquisition Date Mar. 11, 2019 [5] Mar. 11, 2019 [6]        
Shares | shares 453,641 560,536 453,641 560,536    
Software | Demandbase, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 545,000 [1] $ 404,000 [2]        
Investments at Fair Value $ 140,000 $ 443,000        
Investment, Acquisition Date Aug. 02, 2021 [5] Aug. 02, 2021 [6]        
Shares | shares 727,047 483,248 727,047 483,248    
Software | Eigen Technologies Ltd. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[29],[30] $ 8,000          
Investments at Fair Value [29],[30] $ 8,000          
Investment, Acquisition Date [5] Apr. 13, 2022          
Shares | shares [29],[30] 522   522      
Software | Esme Learning Solutions, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 198,000          
Investments at Fair Value $ 0          
Investment, Acquisition Date [5] Jan. 27, 2022          
Shares | shares 56,765   56,765      
Software | Mixpanel, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 252,000 [1] $ 252,000 [2]        
Investments at Fair Value $ 233,000 $ 906,000        
Investment, Acquisition Date Sep. 30, 2020 [5] Sep. 30, 2020 [6]        
Shares | shares 82,362 82,362 82,362 82,362    
Software | Nuvolo Technologies Corporation | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 172,000 [1] $ 88,000 [2]        
Investments at Fair Value $ 190,000 $ 283,000        
Investment, Acquisition Date Mar. 29, 2019 [5] Mar. 29, 2019 [6]        
Shares | shares 70,000 50,000 70,000 50,000    
Software | Pollen, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Principal Amount   $ 20,498,000        
Investment cost $ 21,030,000 [1] 20,533,000 [2]        
Investments at Fair Value 22,014,000 20,406,000        
Software | Tact.ai Technologies, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost 206,000 [1] 206,000 [2]        
Investments at Fair Value $ 90,000 $ 162,000        
Investment, Acquisition Date Feb. 13, 2020 [5] Feb. 13, 2020 [6]        
Shares | shares 1,041,667 1,041,667 1,041,667 1,041,667    
Software | Udacity, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 218,000 [1] $ 218,000 [2]        
Investments at Fair Value $ 21,000 $ 345,000        
Investment, Acquisition Date Sep. 25, 2020 [5] Sep. 25, 2020 [6]        
Shares | shares 486,359 486,359 486,359 486,359    
Software | VideoAmp, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[31] $ 1,275,000          
Investments at Fair Value [31] $ 416,000          
Investment, Acquisition Date [5] Jan. 21, 2022          
Shares | shares [31] 152,048   152,048      
Software | Zimperium, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [2]   $ 72,000        
Investments at Fair Value   $ 56,000        
Investment, Acquisition Date [6]   Jul. 02, 2021        
Shares | shares   20,563   20,563    
Software | SingleStore, Inc. | Equity            
Investment Holdings [Line Items]            
Investment cost $ 2,280,000 [1] $ 2,279,000 [2]        
Investments at Fair Value $ 1,428,000 $ 2,479,000        
Shares | shares 633,939 633,939 633,939 633,939    
Software | SingleStore, Inc. | Equity | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost $ 2,000,000 [1] $ 2,000,000 [2]        
Investments at Fair Value $ 1,278,000 $ 2,239,000        
Investment, Acquisition Date Nov. 25, 2020 [5] Nov. 25, 2020 [6]        
Shares | shares 580,983 580,983 580,983 580,983    
Software | SingleStore, Inc. | Equity | Preferred Series F            
Investment Holdings [Line Items]            
Investment cost $ 280,000 [1] $ 279,000 [2]        
Investments at Fair Value $ 150,000 $ 240,000        
Investment, Acquisition Date Aug. 12, 2021 [5] Aug. 12, 2021 [6]        
Shares | shares 52,956 52,956 52,956 52,956    
Software | SingleStore, Inc. | Warrant Investment | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost $ 103,000 [1] $ 103,000 [2]        
Investments at Fair Value $ 258,000 $ 704,000        
Investment, Acquisition Date Apr. 28, 2020 [5] Apr. 28, 2020 [6]        
Shares | shares 312,596 312,596 312,596 312,596    
Software | CapLinked, Inc. | Equity | Preferred Series A-3            
Investment Holdings [Line Items]            
Investment cost $ 51,000 [1] $ 51,000 [2]        
Investments at Fair Value $ 5,000 $ 65,000        
Investment, Acquisition Date Oct. 26, 2012 [5] Oct. 26, 2012 [6]        
Shares | shares 53,614 53,614 53,614 53,614    
Software | Docker, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 4,284,000 [1] $ 4,284,000 [2]        
Investments at Fair Value $ 494,000 $ 3,000        
Investment, Acquisition Date Nov. 29, 2018 [5] Nov. 29, 2018 [6]        
Shares | shares 20,000 20,000 20,000 20,000    
Software | Druva Holdings, Inc. | Equity            
Investment Holdings [Line Items]            
Investment cost $ 1,300,000 [1] $ 1,300,000 [2]        
Investments at Fair Value $ 1,758,000 $ 2,916,000        
Shares | shares 552,461 552,461 552,461 552,461    
Software | Druva Holdings, Inc. | Equity | Preferred Series 3            
Investment Holdings [Line Items]            
Investment cost $ 300,000 [1] $ 300,000 [2]        
Investments at Fair Value $ 330,000 $ 529,000        
Investment, Acquisition Date Aug. 24, 2017 [5] Aug. 24, 2017 [6]        
Shares | shares 93,620 93,620 93,620 93,620    
Software | Druva Holdings, Inc. | Equity | Preferred Series 2            
Investment Holdings [Line Items]            
Investment cost $ 1,000,000 [1] $ 1,000,000 [2]        
Investments at Fair Value $ 1,428,000 $ 2,387,000        
Investment, Acquisition Date Oct. 22, 2015 [5] Oct. 22, 2015 [6]        
Shares | shares 458,841 458,841 458,841 458,841    
Software | HighRoads, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 307,000 [1] $ 307,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Jan. 18, 2013 [5] Jan. 18, 2013 [6]        
Shares | shares 190 190 190 190    
Software | Lightbend, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 265,000 [1] $ 265,000 [2]        
Investments at Fair Value $ 14,000 $ 5,000        
Investment, Acquisition Date Dec. 04, 2020 [5] Dec. 04, 2020 [6]        
Shares | shares 38,461 38,461 38,461 38,461    
Software | Lightbend, Inc. | Warrant Investment | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost $ 131,000 [1] $ 131,000 [2]        
Investments at Fair Value $ 1,000 $ 0        
Investment, Acquisition Date Feb. 14, 2018 [5] Feb. 14, 2018 [6]        
Shares | shares 89,685 89,685 89,685 89,685    
Software | Palantir Technologies | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 8,670,000 [1],[5] $ 8,670,000 [2],[6]        
Investments at Fair Value $ 11,531,000 [5] $ 25,828,000 [6]        
Investment, Acquisition Date Sep. 23, 2020 [5] Sep. 23, 2020 [6]        
Shares | shares 1,418,337 [5] 1,418,337 [6] 1,418,337 [5] 1,418,337 [6]    
Software | Sprinklr, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 3,748,000 [1],[5] $ 3,749,000 [2],[6]        
Investments at Fair Value $ 6,454,000 [5] $ 11,109,000 [6]        
Investment, Acquisition Date Mar. 22, 2017 [5] Mar. 22, 2017 [6]        
Shares | shares 700,000 [5] 700,000 [6] 700,000 [5] 700,000 [6]    
Software | Verana Health, Inc. | Equity | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost $ 2,000,000 [1] $ 2,000,000 [2]        
Investments at Fair Value $ 1,171,000 $ 1,697,000        
Investment, Acquisition Date Jul. 08, 2021 [5] Jul. 08, 2021 [6]        
Shares | shares 952,562 952,562 952,562 952,562    
Software | Bitsight Technologies Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 284,000 [1] $ 284,000 [2]        
Investments at Fair Value $ 597,000 $ 1,272,000        
Investment, Acquisition Date Nov. 18, 2020 [5] Nov. 18, 2020 [6]        
Shares | shares 29,691 29,691 29,691 29,691    
Software | Cloudian Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 71,000 [1] $ 71,000 [2]        
Investments at Fair Value $ 17,000 $ 33,000        
Investment, Acquisition Date Nov. 06, 2018 [5] Nov. 06, 2018 [6]        
Shares | shares 477,454 477,454 477,454 477,454    
Software | Dronedeploy Incorporation | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 278,000          
Investments at Fair Value $ 307,000          
Investment, Acquisition Date [5] Jun. 30, 2022          
Shares | shares 95,911   95,911      
Software | Evernote Corporation | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 107,000 [1] $ 106,000 [2]        
Investments at Fair Value $ 15,000 $ 65,000        
Investment, Acquisition Date Sep. 30, 2016 [5] Sep. 30, 2016 [6]        
Shares | shares 62,500 62,500 62,500 62,500    
Software | Poplicus Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 0 [1] $ 0 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date May 28, 2014 [5] May 28, 2014 [6]        
Shares | shares 132,168 132,168 132,168 132,168    
Software | Reltio Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 215,000 [1] $ 215,000 [2]        
Investments at Fair Value $ 296,000 $ 637,000        
Investment, Acquisition Date Jun. 30, 2020 [5] Jun. 30, 2020 [6]        
Shares | shares 69,120 69,120 69,120 69,120    
Software | Sign Post Inc | Warrant Investment | Series Junior 1 Preferred            
Investment Holdings [Line Items]            
Investment cost $ 314,000 [1] $ 314,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Jan. 13, 2016 [5] Jan. 13, 2016 [6]        
Shares | shares 474,019 474,019 474,019 474,019    
Software | Zero Fox Inc | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5],[22] $ 101,000          
Investments at Fair Value [5],[22] $ 1,467,000          
Investment, Acquisition Date [5] May 07, 2020          
Shares | shares [5],[22] 289,992   289,992      
Software | Zero Fox Inc | Warrant Investment | Preferred Series C-1            
Investment Holdings [Line Items]            
Investment cost [2]   $ 101,000        
Investments at Fair Value   $ 603,000        
Investment, Acquisition Date [6]   May 07, 2020        
Shares | shares   648,350   648,350    
Software | Couchbase Inc | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 462,000 [1],[5] $ 462,000 [2],[6],[34]        
Investments at Fair Value $ 563,000 [5] $ 1,343,000 [6],[34]        
Investment, Acquisition Date Apr. 25, 2019 [5] Apr. 25, 2019 [6]        
Shares | shares 105,350 [5] 105,350 [6],[34] 105,350 [5] 105,350 [6],[34]    
Software | D N Anexus Inc | Warrant Investment | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 97,000 [1] $ 97,000 [2]        
Investments at Fair Value $ 114,000 $ 102,000        
Investment, Acquisition Date Mar. 21, 2014 [5] Mar. 21, 2014 [6]        
Shares | shares 909,091 909,091 909,091 909,091    
Software | Fuze, Inc. | Warrant Investment | Preferred Series F            
Investment Holdings [Line Items]            
Investment cost [2]   $ 89,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Jun. 30, 2017        
Shares | shares   256,158   256,158    
Software | Rapid Miner Inc | Warrant Investment | Preferred Series C-1            
Investment Holdings [Line Items]            
Investment cost [2]   $ 24,000        
Investments at Fair Value   $ 54,000        
Investment, Acquisition Date [6]   Nov. 28, 2017        
Shares | shares   4,982   4,982    
Software | Senior Secured | Automation Anywhere, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-09   2027-09      
Investment, Basis Spread, Variable Rate [7] 4.25%   4.25%      
Investment, Interest Rate, Floor [7] 9.00%   9.00%      
Principal Amount [8],[10] $ 19,600,000          
Investment cost [1],[8],[10] 19,008,000          
Investments at Fair Value [8],[10] $ 19,008,000          
Software | Senior Secured | Constructor.io Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-07   2027-07      
Investment, Basis Spread, Variable Rate [7] 8.44%   8.44%      
Investment, Interest Rate, Floor [7] 9.44%   9.44%      
Principal Amount [10],[13] $ 4,688,000          
Investment cost [1],[10],[13] 4,569,000          
Investments at Fair Value [10],[13] $ 4,569,000          
Software | Senior Secured | Omeda Holdings, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-07   2027-07      
Investment, Basis Spread, Variable Rate [7] 8.05%   8.05%      
Investment, Interest Rate, Floor [7] 9.05%   9.05%      
Principal Amount [10],[13] $ 7,500,000          
Investment cost [1],[10],[13] 7,251,000          
Investments at Fair Value [10],[13] $ 7,251,000          
Software | Senior Secured | Cutover, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-10   2025-10      
Investment, Basis Spread, Variable Rate [7] 5.20%   5.20%      
Investment, Interest Rate, Floor [7] 9.95%   9.95%      
Principal Amount [29],[30] $ 5,000,000          
Investment cost [1],[29],[30] 4,927,000          
Investments at Fair Value [29],[30] $ 4,927,000          
Software | Senior Secured | Delphix Corp. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2023-02   2023-02    
Investment Interest Rate [11]   5.00%   5.00%    
Investment, Basis Spread, Variable Rate [11]   5.50%   5.50%    
Investment, Interest Rate, Floor [11]   10.25%   10.25%    
Interest Rate and Floor [11]   5.00%   5.00%    
Principal Amount [21],[23],[33]   $ 60,000,000        
Investment cost [2],[21],[23],[33]   61,736,000        
Investments at Fair Value [21],[23],[33]   $ 62,345,000        
Software | Senior Secured | Khoros (p.k.a Lithium Technologies) | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date   2022-10   2022-10    
Investment, Basis Spread, Variable Rate [11]   8.00%   8.00%    
Investment, Interest Rate, Floor [11]   9.00%   9.00%    
Principal Amount [15]   $ 56,208,000        
Investment cost [2],[15]   55,834,000        
Investments at Fair Value [15]   $ 55,834,000        
Software | Senior Secured | Khoros (p.k.a Lithium Technologies) | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-01   2024-01      
Principal Amount [10] $ 56,208,000          
Investment cost [1],[10] 56,028,000          
Investments at Fair Value [10] $ 55,958,000          
Software | Senior Secured | Pymetrics, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date   2022-10   2022-10    
Investment Interest Rate [11]   4.00%   4.00%    
Investment, Basis Spread, Variable Rate [11]   5.50%   5.50%    
Investment, Interest Rate, Floor [11]   8.75%   8.75%    
Investment, Interest Rate, Paid in Kind [11]   1.75%   1.75%    
Interest Rate and Floor [11]   4.00%   4.00%    
Principal Amount [20]   $ 9,667,000        
Investment cost [2],[20]   9,845,000        
Investments at Fair Value [20]   $ 9,845,000        
Software | Senior Secured | 3GTMS, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-02 2025-02 2025-02 2025-02    
Investment, Basis Spread, Variable Rate 9.28% [7] 9.28% [11] 9.28% [7] 9.28% [11]    
Investment, Interest Rate, Floor 10.28% [7] 10.28% [11] 10.28% [7] 10.28% [11]    
Principal Amount $ 10,808,000 [10],[12],[13] $ 10,000,000 [15],[16]        
Investment cost 10,660,000 [1],[10],[12],[13] 9,812,000 [2],[15],[16]        
Investments at Fair Value $ 10,496,000 [10],[12],[13] $ 9,656,000 [15],[16]        
Software | Senior Secured | Agilence, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-10 2026-10 2026-10 2026-10    
Investment, Basis Spread, Variable Rate 9.00% [7] 9.00% [11] 9.00% [7] 9.00% [11]    
Investment, Interest Rate, Floor 10.00% [7] 10.00% [11] 10.00% [7] 10.00% [11]    
Principal Amount $ 9,330,000 [10],[13],[18] $ 9,400,000 [15]        
Investment cost 9,100,000 [1],[10],[13],[18] 9,138,000 [2],[15]        
Investments at Fair Value $ 8,880,000 [10],[13],[18] $ 9,138,000 [15]        
Software | Senior Secured | Annex Cloud | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-02   2027-02      
Investment, Basis Spread, Variable Rate [7] 9.00%   9.00%      
Investment, Interest Rate, Floor [7] 10.00%   10.00%      
Principal Amount [10],[17] $ 8,500,000          
Investment cost [1],[10],[17] 8,282,000          
Investments at Fair Value [10],[17] $ 8,148,000          
Software | Senior Secured | Brain Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-04 2025-04 2025-04 2025-04    
Investment Interest Rate [11]   3.95%   3.95%    
Investment, Basis Spread, Variable Rate 3.70% [7] 3.70% [11] 3.70% [7] 3.70% [11]    
Investment, Interest Rate, Floor 6.95% [7] 6.95% [11] 6.95% [7] 6.95% [11]    
Investment, Interest Rate, Paid in Kind 1.00% [7] 1.00% [11] 1.00% [7] 1.00% [11]    
Interest Rate and Floor [11]   3.95%   3.95%    
Principal Amount $ 20,116,000 [9],[10],[17],[31] $ 10,016,000 [15],[20],[32]        
Investment cost 20,101,000 [1],[9],[10],[17],[31] 9,943,000 [2],[15],[20],[32]        
Investments at Fair Value $ 20,196,000 [9],[10],[17],[31] $ 9,943,000 [15],[20],[32]        
Software | Senior Secured | Campaign Monitor Limited | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-11 2025-11 2025-11 2025-11    
Investment, Basis Spread, Variable Rate 8.90% [7] 7.90% [11] 8.90% [7] 7.90% [11]    
Investment, Interest Rate, Floor 9.90% [7] 11.15% [11] 9.90% [7] 11.15% [11]    
Principal Amount $ 33,000,000 [8],[17] $ 33,000,000 [23]        
Investment cost 32,546,000 [1],[8],[17] 32,459,000 [2],[23]        
Investments at Fair Value $ 32,944,000 [8],[17] $ 33,000,000 [23]        
Software | Senior Secured | Catchpoint Systems, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-06   2026-06      
Investment, Basis Spread, Variable Rate [7] 8.76%   8.76%      
Investment, Interest Rate, Floor [7],[10],[13] 9.76%   9.76%      
Principal Amount [13] $ 10,200,000          
Investment cost [1],[13] 10,034,000          
Investments at Fair Value [13] $ 10,043,000          
Software | Senior Secured | Ceros, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-09 2026-09 2026-09 2026-09    
Investment, Basis Spread, Variable Rate 8.89% [7] 8.89% [11] 8.89% [7] 8.89% [11]    
Investment, Interest Rate, Floor 9.89% [7],[10],[13] 9.89% [11] 9.89% [7],[10],[13] 9.89% [11]    
Principal Amount $ 19,855,000 [10],[13] $ 17,978,000 [15],[16]        
Investment cost 19,420,000 [1],[10],[13] 17,474,000 [2],[15],[16]        
Investments at Fair Value $ 19,482,000 [10],[13] $ 17,474,000 [15],[16]        
Software | Senior Secured | CloudBolt Software, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-10 2024-10 2024-10 2024-10    
Investment Interest Rate [11]   2.95%   2.95%    
Investment, Basis Spread, Variable Rate 6.70% [7] 6.70% [11] 6.70% [7] 6.70% [11]    
Investment, Interest Rate, Floor 9.95% [7] 9.95% [11] 9.95% [7] 9.95% [11]    
Interest Rate and Floor [11]   2.95%   2.95%    
Principal Amount $ 10,000,000 [8],[12],[18] $ 10,000,000 [14],[23],[33]        
Investment cost 10,021,000 [1],[8],[12],[18] 9,923,000 [2],[14],[23],[33]        
Investments at Fair Value $ 10,014,000 [8],[12],[18] $ 10,035,000 [14],[23],[33]        
Software | Senior Secured | Copper CRM, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-03   2025-03      
Investment, Basis Spread, Variable Rate [7] 4.50%   4.50%      
Investment, Interest Rate, Floor [7] 8.25%   8.25%      
Investment, Interest Rate, Paid in Kind [7] 1.95%   1.95%      
Principal Amount [9],[12] $ 10,095,000          
Investment cost [1],[9],[12] 10,058,000          
Investments at Fair Value [9],[12] $ 9,882,000          
Software | Senior Secured | Cybermaxx Intermediate Holdings, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-08 2026-08 2026-08 2026-08    
Investment, Basis Spread, Variable Rate 9.28% [7] 9.28% [11] 9.28% [7] 9.28% [11]    
Investment, Interest Rate, Floor 10.28% [7] 10.28% [11] 10.28% [7] 10.28% [11]    
Principal Amount $ 7,980,000 [10],[17] $ 8,000,000 [15]        
Investment cost 7,808,000 [1],[10],[17] 7,801,000 [2],[15]        
Investments at Fair Value $ 7,732,000 [10],[17] $ 7,801,000 [15]        
Software | Senior Secured | Dashlane, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-07 2025-07 2025-07 2025-07    
Investment Interest Rate [11]   7.10%   7.10%    
Investment, Basis Spread, Variable Rate 3.05% [7] 3.05% [11] 3.05% [7] 3.05% [11]    
Investment, Interest Rate, Floor 7.55% [7] 7.55% [11] 7.55% [7] 7.55% [11]    
Investment, Interest Rate, Paid in Kind 1.10% [7] 1.10% [11] 1.10% [7] 1.10% [11]    
Interest Rate and Floor [11]   7.10%   7.10%    
Principal Amount $ 31,841,000 [8],[9],[10],[12],[17] $ 20,719,000 [14],[15],[20],[23]        
Investment cost 32,186,000 [1],[8],[9],[10],[12],[17] 21,807,000 [2],[14],[15],[20],[23]        
Investments at Fair Value $ 31,580,000 [8],[9],[10],[12],[17] $ 21,734,000 [14],[15],[20],[23]        
Software | Senior Secured | Demandbase, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-08 2025-08 2025-08 2025-08    
Investment, Basis Spread, Variable Rate 2.25% [7] 5.25% [11] 2.25% [7] 5.25% [11]    
Investment, Interest Rate, Floor 5.50% [7] 8.50% [11] 5.50% [7] 8.50% [11]    
Investment, Interest Rate, Paid in Kind [7] 3.00%   3.00%      
Principal Amount $ 28,288,000 [8],[9],[10],[17] $ 16,875,000 [15],[23]        
Investment cost 28,010,000 [1],[8],[9],[10],[17] 16,463,000 [2],[15],[23]        
Investments at Fair Value $ 28,187,000 [8],[9],[10],[17] $ 16,463,000 [15],[23]        
Software | Senior Secured | Eigen Technologies Ltd. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-04   2025-04      
Investment, Basis Spread, Variable Rate [7] 5.10%   5.10%      
Investment, Interest Rate, Floor [7] 8.35%   8.35%      
Principal Amount [29],[30] $ 3,750,000          
Investment cost [1],[29],[30] 3,730,000          
Investments at Fair Value [29],[30] $ 3,726,000          
Software | Senior Secured | Enmark Systems, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-09 2026-09 2026-09 2026-09    
Investment, Basis Spread, Variable Rate 6.83% [7] 6.83% [11] 6.83% [7] 6.83% [11]    
Investment, Interest Rate, Floor 7.83% [7] 7.83% [11] 7.83% [7] 7.83% [11]    
Investment, Interest Rate, Paid in Kind 2.19% [7] 2.19% [11] 2.19% [7] 2.19% [11]    
Principal Amount $ 8,178,000 [9],[10],[12],[13] $ 8,000,000 [14],[15],[16]        
Investment cost 8,001,000 [1],[9],[10],[12],[13] 7,798,000 [2],[14],[15],[16]        
Investments at Fair Value $ 7,948,000 [9],[10],[12],[13] $ 7,798,000 [14],[15],[16]        
Software | Senior Secured | Esentire, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-05 2024-05 2024-05 2024-05    
Investment, Basis Spread, Variable Rate 9.96% [7] 9.96% [11],[27],[28] 9.96% [7] 9.96% [11],[27],[28]    
Investment, Interest Rate, Floor 10.96% [7] 10.96% [11],[27],[28] 10.96% [7] 10.96% [11],[27],[28]    
Principal Amount $ 8,468,000 [12],[13],[29],[30] $ 21,000,000 [14],[16],[27],[28]        
Investment cost 8,380,000 [1],[12],[13],[29],[30] 20,699,000 [2],[14],[16],[27],[28]        
Investments at Fair Value $ 8,425,000 [12],[13],[29],[30] $ 20,750,000 [14],[16],[27],[28]        
Software | Senior Secured | Esme Learning Solutions, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-02   2025-02      
Investment, Basis Spread, Variable Rate [7] 5.50%   5.50%      
Investment, Interest Rate, Floor [7] 8.75%   8.75%      
Investment, Interest Rate, Paid in Kind [7] 1.50%   1.50%      
Principal Amount [9] $ 5,045,000          
Investment cost [1],[9] 4,890,000          
Investments at Fair Value [9] $ 4,270,000          
Software | Senior Secured | Gryphon Networks Corp. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-01 2026-01 2026-01 2026-01    
Investment, Basis Spread, Variable Rate 9.69% [7] 9.69% [11] 9.69% [7] 9.69% [11]    
Investment, Interest Rate, Floor 10.69% [7] 10.69% [11] 10.69% [7] 10.69% [11]    
Principal Amount $ 5,232,000 [10],[12] $ 5,232,000 [14],[15]        
Investment cost 5,125,000 [1],[10],[12] 5,106,000 [2],[14],[15]        
Investments at Fair Value $ 5,258,000 [10],[12] $ 5,088,000 [14],[15]        
Software | Senior Secured | Ikon Science Limited | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-10 2024-10 2024-10 2024-10    
Investment, Basis Spread, Variable Rate 9.00% [7] 9.00% [11],[27],[28] 9.00% [7] 9.00% [11],[27],[28]    
Investment, Interest Rate, Floor [7] 10.00%   10.00%      
Principal Amount $ 6,650,000 [10],[13],[29],[30] $ 6,913,000 [15],[16],[27],[28]        
Investment cost 6,510,000 [1],[10],[13],[29],[30] 6,719,000 [2],[15],[16],[27],[28]        
Investments at Fair Value $ 6,572,000 [10],[13],[29],[30] $ 6,767,000 [15],[16],[27],[28]        
Software | Senior Secured | Imperva, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-01   2027-01      
Investment, Basis Spread, Variable Rate [7] 8.75%   8.75%      
Investment, Interest Rate, Floor [7] 7.75%   7.75%      
Principal Amount [8] $ 20,000,000          
Investment cost [1],[8] 19,869,000          
Investments at Fair Value [8] $ 20,000,000          
Software | Senior Secured | Imperva, Inc. | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2027-01   2027-01    
Investment, Basis Spread, Variable Rate [11]   7.75%   7.75%    
Investment, Interest Rate, Floor [11]   8.75%   8.75%    
Principal Amount [23]   $ 20,000,000        
Investment cost [2],[23]   19,851,000        
Investments at Fair Value [23]   $ 20,000,000        
Software | Senior Secured | Kazoo, Inc. (p.k.a. YouEarnedIt, Inc.) | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date 2023-07   2023-07      
Investment, Basis Spread, Variable Rate [7] 10.15%   10.15%      
Investment, Interest Rate, Floor [7] 11.15%   11.15%      
Principal Amount [13] $ 10,819,000          
Investment cost [1],[13] 10,691,000          
Investments at Fair Value [13] $ 10,691,000          
Software | Senior Secured | Kazoo, Inc. (p.k.a. YouEarnedIt, Inc.) | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2023-07   2023-07    
Investment, Basis Spread, Variable Rate 8.00% [7] 10.14% [11] 8.00% [7] 10.14% [11]    
Investment, Interest Rate, Floor 9.00% [7] 11.14% [11] 9.00% [7] 11.14% [11]    
Principal Amount [16]   $ 8,571,000        
Investment cost [2],[16]   8,403,000        
Investments at Fair Value [16]   $ 8,375,000        
Software | Senior Secured | Logicworks | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-01 2024-01 2024-01 2024-01    
Investment Interest Rate [7] 0.75%   0.75%      
Investment, Basis Spread, Variable Rate 7.50% [7] 7.50% [11] 7.50% [7] 7.50% [11]    
Investment, Interest Rate, Floor [11]   10.75%   10.75%    
Interest Rate and Floor [7] 0.75%   0.75%      
Principal Amount $ 14,500,000 [18] $ 10,000,000 [15],[33]        
Investment cost 14,373,000 [1],[18] 9,862,000 [2],[15],[33]        
Investments at Fair Value $ 14,356,000 [18] $ 9,965,000 [15],[33]        
Software | Senior Secured | Mixpanel, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-08 2024-08 2024-08 2024-08    
Investment Interest Rate [11]   3.00%   3.00%    
Investment, Basis Spread, Variable Rate 4.70% [7] 4.70% [11] 4.70% [7] 4.70% [11]    
Investment, Interest Rate, Floor 7.95% [7] 7.95% [11] 7.95% [7] 7.95% [11]    
Investment, Interest Rate, Paid in Kind 1.80% [7] 1.80% [11] 1.80% [7] 1.80% [11]    
Interest Rate and Floor [11]   3.00%   3.00%    
Principal Amount $ 20,713,000 [8],[9] $ 20,431,000 [20],[23],[33]        
Investment cost 20,755,000 [1],[8],[9] 20,292,000 [2],[20],[23],[33]        
Investments at Fair Value $ 21,554,000 [8],[9] $ 21,030,000 [20],[23],[33]        
Software | Senior Secured | Mobile Solutions Services | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-12 2025-12 2025-12 2025-12    
Investment, Basis Spread, Variable Rate 9.06% [7] 9.87% [11] 9.06% [7] 9.87% [11]    
Investment, Interest Rate, Floor 10.06% [7] 10.87% [11] 10.06% [7] 10.87% [11]    
Principal Amount $ 17,668,000 [10],[13] $ 19,074,000 [15],[16]        
Investment cost 17,283,000 [1],[10],[13] 18,575,000 [2],[15],[16]        
Investments at Fair Value $ 16,984,000 [10],[13] $ 18,834,000 [15],[16]        
Software | Senior Secured | Nuvolo Technologies Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-07 2025-07 2025-07 2025-07    
Investment Interest Rate [11]   1.75%   1.75%    
Investment, Basis Spread, Variable Rate 5.25% [7] 7.70% [11] 5.25% [7] 7.70% [11]    
Investment, Interest Rate, Floor 8.50% [7] 10.95% [11] 8.50% [7] 10.95% [11]    
Interest Rate and Floor [11]   1.75%   1.75%    
Principal Amount $ 17,500,000 [8],[10],[17],[18] $ 15,000,000 [23],[33]        
Investment cost 17,525,000 [1],[8],[10],[17],[18] 14,967,000 [2],[23],[33]        
Investments at Fair Value 17,586,000 [8],[10],[17],[18] $ 15,017,000 [23],[33]        
Software | Senior Secured | Pollen, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Principal Amount $ 20,662,000          
Software | Senior Secured | Riviera Partners LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-04   2027-04      
Investment, Basis Spread, Variable Rate [7] 7.53%   7.53%      
Investment, Interest Rate, Floor [7] 8.53%   8.53%      
Principal Amount [10],[13] $ 26,184,000          
Investment cost [1],[10],[13] 25,595,000          
Investments at Fair Value [10],[13] $ 25,595,000          
Software | Senior Secured | ShadowDragon, LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-12 2026-12 2026-12 2026-12    
Investment, Basis Spread, Variable Rate 9.00% [7] 9.00% [11] 9.00% [7] 9.00% [11]    
Investment, Interest Rate, Floor 10.00% [7] 10.00% [11] 10.00% [7] 10.00% [11]    
Principal Amount $ 6,000,000 [13] $ 6,000,000 [15],[16]        
Investment cost 5,849,000 [1],[13] 5,828,000 [2],[15],[16]        
Investments at Fair Value $ 5,780,000 [13] $ 5,828,000 [15],[16]        
Software | Senior Secured | Tact.ai Technologies, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-02 2024-02 2024-02 2024-02    
Investment Interest Rate [11]   5.50%   5.50%    
Investment, Basis Spread, Variable Rate 4.00% [7] 4.00% [11] 4.00% [7] 4.00% [11]    
Investment, Interest Rate, Floor 8.75% [7] 8.75% [11] 8.75% [7] 8.75% [11]    
Investment, Interest Rate, Paid in Kind 2.00% [7] 2.00% [11] 2.00% [7] 2.00% [11]    
Interest Rate and Floor [11]   5.50%   5.50%    
Principal Amount $ 5,009,000 [9] $ 5,185,000 [20]        
Investment cost 5,213,000 [1],[9] 5,305,000 [2],[20]        
Investments at Fair Value $ 4,885,000 [9] $ 5,245,000 [33]        
Software | Senior Secured | ThreatConnect, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2026-05 2026-05 2026-05 2026-05    
Investment, Basis Spread, Variable Rate 9.00% [7] 9.00% [11] 9.00% [7] 9.00% [11]    
Investment, Interest Rate, Floor 10.00% [7] 10.00% [11] 10.00% [7] 10.00% [11]    
Principal Amount $ 11,060,000 [10],[13],[18] $ 11,144,000 [15],[16],[33]        
Investment cost 10,791,000 [1],[10],[13],[18] 10,831,000 [2],[15],[16],[33]        
Investments at Fair Value $ 10,832,000 [10],[13],[18] $ 10,859,000 [15],[16],[33]        
Software | Senior Secured | Udacity, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-09 2024-09 2024-09 2024-09    
Investment Interest Rate [11]   3.00%   3.00%    
Investment, Basis Spread, Variable Rate 4.50% [7] 4.50% [11] 4.50% [7] 4.50% [11]    
Investment, Interest Rate, Floor 7.75% [7] 7.75% [11] 7.75% [7] 7.75% [11]    
Investment, Interest Rate, Paid in Kind 2.00% [7] 2.00% [11] 2.00% [7] 2.00% [11]    
Interest Rate and Floor [11]   3.00%   3.00%    
Principal Amount $ 51,675,000 [9],[18] $ 50,895,000 [20],[33]        
Investment cost 51,851,000 [1],[9],[18] 50,646,000 [2],[20],[33]        
Investments at Fair Value $ 52,330,000 [9],[18] $ 51,722,000 [20],[33]        
Software | Senior Secured | VideoAmp, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-02   2025-02      
Investment, Basis Spread, Variable Rate [7] 3.70%   3.70%      
Investment, Interest Rate, Floor [7] 6.95%   6.95%      
Investment, Interest Rate, Paid in Kind [7] 1.25%   1.25%      
Principal Amount [8],[9],[31] $ 62,987,000          
Investment cost [1],[8],[9],[31] 62,056,000          
Investments at Fair Value [8],[9],[31] $ 62,467,000          
Software | Senior Secured | Zimperium, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2027-05 2024-07 2027-05 2024-07    
Investment, Basis Spread, Variable Rate 8.31% [7] 8.95% [11] 8.31% [7] 8.95% [11]    
Investment, Interest Rate, Floor 9.31% [7] 9.95% [11] 9.31% [7] 9.95% [11]    
Principal Amount $ 16,313,000 [10],[13] $ 15,633,000 [16],[33]        
Investment cost 15,984,000 [1],[10],[13] 15,347,000 [2],[16],[33]        
Investments at Fair Value $ 15,984,000 [10],[13] $ 15,347,000 [16],[33]        
Software | Senior Secured | Alchemer LLC | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2028-05   2028-05      
Investment, Basis Spread, Variable Rate [7] 7.89%   7.89%      
Investment, Interest Rate, Floor [7] 8.89%   8.89%      
Principal Amount [10],[13] $ 15,125,000          
Investment cost [1],[10],[13] 14,778,000          
Investments at Fair Value [10],[13] $ 14,778,000          
Software | Senior Secured | Dispatch Technologies, Inc. | Greater than 5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2028-04   2028-04      
Investment, Basis Spread, Variable Rate [7] 8.01%   8.01%      
Investment, Interest Rate, Floor [7] 8.76%   8.76%      
Principal Amount [10],[13] $ 7,500,000          
Investment cost [1],[10],[13] 7,288,000          
Investments at Fair Value [10],[13] $ 7,288,000          
Software | Senior Secured | Reltio Inc | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2023-07   2023-07    
Investment Interest Rate [11]   4.95%   4.95%    
Investment, Basis Spread, Variable Rate [11]   5.70%   5.70%    
Investment, Interest Rate, Floor [11]   8.95%   8.95%    
Investment, Interest Rate, Paid in Kind [11]   1.70%   1.70%    
Interest Rate and Floor [11]   4.95%   4.95%    
Principal Amount [20],[23]   $ 10,248,000        
Investment cost [2],[20],[23]   10,336,000        
Investments at Fair Value [20],[23]   $ 10,542,000        
Software | Senior Secured | Regent Education | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date   2022-01   2022-01    
Investment, Interest Rate, Paid in Cash [11],[37]   10.00%   10.00%    
Investment Interest Rate [11],[37]   7.94%   7.94%    
Investment, Interest Rate, Paid in Kind [11],[37]   2.00%   2.00%    
Interest Rate and Floor [11],[37]   7.94%   7.94%    
Principal Amount [20],[37]   $ 2,951,000        
Investment cost [2],[20],[37]   3,064,000        
Investments at Fair Value [20],[37]   $ 2,608,000        
Software | Senior Secured | Cloud 9 Software | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date   2024-04   2024-04    
Investment, Basis Spread, Variable Rate [11]   8.20%   8.20%    
Investment, Interest Rate, Floor [11]   9.20%   9.20%    
Principal Amount [33]   $ 9,953,000        
Investment cost [2],[33]   9,856,000        
Investments at Fair Value [33]   $ 9,953,000        
Software | Senior Secured | Floor Rate | Ikon Science Limited | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment, Interest Rate, Floor [11],[27],[28]   10.00%   10.00%    
Software | Senior Secured | Exit Fee | Automation Anywhere, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 2.50%   2.50%      
Interest Rate and Floor [7] 2.50%   2.50%      
Software | Senior Secured | Exit Fee | Cutover, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.95%   4.95%      
Interest Rate and Floor [7] 4.95%   4.95%      
Software | Senior Secured | Exit Fee | Brain Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.95%   3.95%      
Interest Rate and Floor [7] 3.95%   3.95%      
Software | Senior Secured | Exit Fee | CloudBolt Software, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.45%   3.45%      
Interest Rate and Floor [7] 3.45%   3.45%      
Software | Senior Secured | Exit Fee | Copper CRM, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.50%   4.50%      
Interest Rate and Floor [7] 4.50%   4.50%      
Software | Senior Secured | Exit Fee | Dashlane, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.95%   4.95%      
Interest Rate and Floor [7] 4.95%   4.95%      
Software | Senior Secured | Exit Fee | Demandbase, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.00%   5.00%      
Investment, Interest Rate, Floor [11]   2.00%   2.00%    
Interest Rate and Floor [7] 5.00%   5.00%      
Software | Senior Secured | Exit Fee | Eigen Technologies Ltd. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 2.95%   2.95%      
Interest Rate and Floor [7] 2.95%   2.95%      
Software | Senior Secured | Exit Fee | Esme Learning Solutions, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.00%   3.00%      
Interest Rate and Floor [7] 3.00%   3.00%      
Software | Senior Secured | Exit Fee | Mixpanel, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.00%   3.00%      
Interest Rate and Floor [7] 3.00%   3.00%      
Software | Senior Secured | Exit Fee | Nuvolo Technologies Corporation | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 2.04%   2.04%      
Interest Rate and Floor [7] 2.04%   2.04%      
Software | Senior Secured | Exit Fee | Tact.ai Technologies, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.50%   5.50%      
Interest Rate and Floor [7] 5.50%   5.50%      
Software | Senior Secured | Exit Fee | Udacity, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.00%   3.00%      
Interest Rate and Floor [7] 3.00%   3.00%      
Software | Senior Secured | Exit Fee | VideoAmp, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 5.25%   5.25%      
Interest Rate and Floor [7] 5.25%   5.25%      
Software | Senior Secured | Cap Rate | Copper CRM, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 10.25%   10.25%      
Interest Rate and Floor [7] 10.25%   10.25%      
Software | Senior Secured Tranche A [Member] | Pollen, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2023-11 2023-11 2023-11 2023-11    
Investment Interest Rate [11]   4.50%   4.50%    
Investment, Basis Spread, Variable Rate 4.75% [7] 4.75% [11] 4.75% [7] 4.75% [11]    
Investment, Interest Rate, Floor 8.00% [7] 8.00% [11] 8.00% [7] 8.00% [11]    
Investment, Interest Rate, Paid in Kind 0.50% [7] 0.50% [11] 0.50% [7] 0.50% [11]    
Interest Rate and Floor [11]   4.50%   4.50%    
Principal Amount $ 7,486,000 [9] $ 7,457,000 [20]        
Investment cost 7,657,000 [1],[9] 7,528,000 [2],[20]        
Investments at Fair Value $ 7,975,000 [9] $ 7,314,000 [20]        
Software | Senior Secured Tranche A [Member] | Exit Fee | Pollen, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.50%   4.50%      
Interest Rate and Floor [7] 4.50%   4.50%      
Software | Senior Secured Tranche B [Member] | Pollen, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2023-11 2023-11 2023-11 2023-11    
Investment Interest Rate [11]   4.50%   4.50%    
Investment, Basis Spread, Variable Rate 5.25% [7] 5.25% [11] 5.25% [7] 5.25% [11]    
Investment, Interest Rate, Floor 8.50% [7] 8.50% [11] 8.50% [7] 8.50% [11]    
Investment, Interest Rate, Paid in Kind 1.35% [7] 1.35% [11] 1.35% [7] 1.35% [11]    
Interest Rate and Floor [11]   4.50%   4.50%    
Principal Amount $ 13,176,000 [9],[31] $ 13,041,000 [20],[32]        
Investment cost 13,373,000 [1],[9],[31] 13,005,000 [2],[20],[32]        
Investments at Fair Value $ 14,039,000 [9],[31] 13,092,000 [20],[32]        
Software | Senior Secured Tranche B [Member] | Exit Fee | Pollen, Inc. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 4.50%   4.50%      
Interest Rate and Floor [7] 4.50%   4.50%      
Software | Debt Investments            
Investment Holdings [Line Items]            
Investment cost $ 647,576,000 [1] 526,253,000 [2]        
Investments at Fair Value 648,620,000 529,402,000        
Sustainable And Renewable Technology            
Investment Holdings [Line Items]            
Investments at Fair Value 15,683,000 39,387,000        
Sustainable And Renewable Technology | Equity            
Investment Holdings [Line Items]            
Investment cost 11,508,000 [1] 12,412,000 [2]        
Investments at Fair Value 8,406,000 11,228,000        
Sustainable And Renewable Technology | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 792,000 [1] 950,000 [2]        
Investments at Fair Value 373,000 1,034,000        
Sustainable And Renewable Technology | Warrant Investment | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost [2]   120,000        
Investments at Fair Value   $ 0        
Investment, Acquisition Date [6]   Jun. 20, 2013        
Shares | shares   471,327   471,327    
Sustainable And Renewable Technology | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment cost [2]   $ 19,659,000        
Investments at Fair Value 6,904,000 19,625,000        
Sustainable And Renewable Technology | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment cost 7,109,000 [1] 7,500,000 [2]        
Investments at Fair Value   7,500,000        
Sustainable And Renewable Technology | Impossible Foods, Inc. | Equity | Series E One Preferred Stock            
Investment Holdings [Line Items]            
Investment cost 2,000,000 [1] 2,000,000 [2]        
Investments at Fair Value $ 2,438,000 $ 3,430,000        
Investment, Acquisition Date May 10, 2019 [5] May 10, 2019 [6]        
Shares | shares 188,611 188,611 188,611 188,611    
Sustainable And Renewable Technology | Impossible Foods, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [11]   9.00%   9.00%    
Investment, Basis Spread, Variable Rate [11]   3.95%   3.95%    
Investment, Interest Rate, Floor [11]   8.95%   8.95%    
Interest Rate and Floor [11]   9.00%   9.00%    
Sustainable And Renewable Technology | Ampion, PBC. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] $ 53,000          
Investments at Fair Value $ 42,000          
Investment, Acquisition Date [5] Apr. 15, 2022          
Shares | shares 18,472   18,472      
Sustainable And Renewable Technology | Pineapple Energy LLC | Equity | Class A Units            
Investment Holdings [Line Items]            
Investment cost [2],[35]   $ 4,767,000        
Investments at Fair Value [35]   $ 591,000        
Investment, Acquisition Date [6],[35]   Dec. 10, 2020        
Shares | shares [35]   3,000,000   3,000,000    
Sustainable And Renewable Technology | Pineapple Energy LLC | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1],[5],[22] $ 3,153,000          
Investments at Fair Value [5],[22] $ 243,000          
Investment, Acquisition Date [5] Dec. 10, 2020          
Shares | shares [5],[22] 304,486   304,486      
Sustainable And Renewable Technology | Pineapple Energy LLC | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Investment, Interest Rate, Paid in Cash [11],[26],[35]   10.00%   10.00%    
Sustainable And Renewable Technology | Pineapple Energy LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment, Interest Rate, Paid in Kind [11],[35],[37]   10.00%   10.00%    
Sustainable And Renewable Technology | Modumetal, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 500,000 [1] $ 500,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Jun. 01, 2015 [5] Jun. 01, 2015 [6]        
Shares | shares 1,035 1,035 1,035 1,035    
Sustainable And Renewable Technology | NantEnergy, LLC | Equity | Common Units            
Investment Holdings [Line Items]            
Investment cost $ 102,000 [1] $ 102,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Aug. 31, 2013 [5] Aug. 31, 2013 [6]        
Shares | shares 59,665 59,665 59,665 59,665    
Sustainable And Renewable Technology | Pivot Bio, Inc. | Equity | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost $ 4,500,000 [1] $ 4,500,000 [2]        
Investments at Fair Value $ 2,571,000 $ 3,164,000        
Investment, Acquisition Date Jun. 28, 2021 [5] Jun. 28, 2021 [6]        
Shares | shares 593,080 593,080 593,080 593,080    
Sustainable And Renewable Technology | Proterra, Inc. | Equity | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 542,000 [1],[5] $ 543,000 [2],[6]        
Investments at Fair Value $ 2,280,000 [5] $ 4,043,000 [6]        
Investment, Acquisition Date May 28, 2015 [5] May 28, 2015 [6]        
Shares | shares 457,841 [5] 457,841 [6] 457,841 [5] 457,841 [6]    
Sustainable And Renewable Technology | Halio Inc            
Investment Holdings [Line Items]            
Investments at Fair Value $ 111,000          
Sustainable And Renewable Technology | Halio Inc | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost [1] $ 218,000          
Shares | shares 456,883   456,883      
Sustainable And Renewable Technology | Halio Inc | Warrant Investment | Preferred Series A            
Investment Holdings [Line Items]            
Investment cost [1] $ 155,000          
Investments at Fair Value $ 83,000          
Investment, Acquisition Date [5] Apr. 22, 2014          
Shares | shares 325,000   325,000      
Sustainable And Renewable Technology | Halio Inc | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost [1] $ 63,000          
Investments at Fair Value $ 28,000          
Investment, Acquisition Date [5] Apr. 07, 2015          
Shares | shares 131,883   131,883      
Sustainable And Renewable Technology | Agrivida Inc | Warrant Investment | Preferred Series D            
Investment Holdings [Line Items]            
Investment cost [1] $ 120,000          
Investments at Fair Value $ 0          
Investment, Acquisition Date [5] Jun. 20, 2013          
Shares | shares 471,327   471,327      
Sustainable And Renewable Technology | Fulcrum Bioenergy Inc | Equity | Preferred Series C-1            
Investment Holdings [Line Items]            
Investment cost [1] $ 711,000          
Investments at Fair Value $ 874,000          
Investment, Acquisition Date [5] Sep. 13, 2012          
Shares | shares 187,265   187,265      
Sustainable And Renewable Technology | Fulcrum Bioenergy Inc | Warrant Investment | Preferred Series C-1            
Investment Holdings [Line Items]            
Investment cost $ 64,000 [1] $ 274,000 [2]        
Investments at Fair Value $ 220,000 $ 699,000        
Investment, Acquisition Date Apr. 30, 2013 [5] Sep. 13, 2012 [6]        
Shares | shares 93,632 280,897 93,632 280,897    
Sustainable And Renewable Technology | Polyera Corporation | Warrant Investment | Preferred Series C            
Investment Holdings [Line Items]            
Investment cost $ 337,000 [1] $ 338,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Dec. 11, 2012 [5] Dec. 11, 2012 [6]        
Shares | shares 311,612 311,609 311,612 311,609    
Sustainable And Renewable Technology | Halio Inc P K Kinestral Technologies Inc | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost [2]   $ 218,000        
Investments at Fair Value   $ 335,000        
Shares | shares   456,883   456,883    
Sustainable And Renewable Technology | Halio Inc P K Kinestral Technologies Inc | Warrant Investment | Preferred Series A            
Investment Holdings [Line Items]            
Investment cost [2]   $ 155,000        
Investments at Fair Value   $ 249,000        
Investment, Acquisition Date [6]   Apr. 22, 2014        
Shares | shares   325,000   325,000    
Sustainable And Renewable Technology | Halio Inc P K Kinestral Technologies Inc | Warrant Investment | Preferred Series B            
Investment Holdings [Line Items]            
Investment cost [2]   $ 63,000        
Investments at Fair Value   $ 86,000        
Investment, Acquisition Date [6]   Apr. 07, 2015        
Shares | shares   131,883   131,883    
Sustainable And Renewable Technology | Senior Secured | Impossible Foods, Inc. | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date   2022-07   2022-07    
Principal Amount [33]   $ 15,022,000        
Investment cost [2],[33]   19,379,000        
Investments at Fair Value [33]   $ 19,378,000        
Sustainable And Renewable Technology | Senior Secured | Ampion, PBC. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2025-05   2025-05      
Investment, Basis Spread, Variable Rate [7] 4.70%   4.70%      
Investment, Interest Rate, Floor [7] 7.95%   7.95%      
Investment, Interest Rate, Paid in Kind [7] 1.45%   1.45%      
Principal Amount [9],[17] $ 4,022,000          
Investment cost [1],[9],[17] 3,953,000          
Investments at Fair Value [9],[17] $ 3,943,000          
Sustainable And Renewable Technology | Senior Secured | Pineapple Energy LLC | Debt Investments Under 1 Year Maturity            
Investment Holdings [Line Items]            
Maturity Date   2022-01   2022-01    
Principal Amount [15],[26],[35]   $ 280,000        
Investment cost [2],[15],[26],[35]   280,000        
Investments at Fair Value [15],[26],[35]   $ 247,000        
Sustainable And Renewable Technology | Senior Secured | Pineapple Energy LLC | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Maturity Date 2024-12 2023-12 2024-12 2023-12    
Investment, Interest Rate, Paid in Kind [7] 10.00%   10.00%      
Principal Amount $ 3,156,000 [9] $ 7,500,000 [15],[20],[35],[37]        
Investment cost 3,156,000 [1],[9] 7,500,000 [2],[15],[20],[35],[37]        
Investments at Fair Value $ 2,961,000 [9] 7,500,000 [15],[20],[35],[37]        
Sustainable And Renewable Technology | Senior Secured | Exit Fee | Ampion, PBC. | Debt Investments 1-5 Years Maturity            
Investment Holdings [Line Items]            
Investment Interest Rate [7] 3.95%   3.95%      
Interest Rate and Floor [7] 3.95%   3.95%      
Sustainable And Renewable Technology | Debt Investments            
Investment Holdings [Line Items]            
Investment cost $ 7,109,000 [1] 27,159,000 [2]        
Investments at Fair Value 6,904,000 27,125,000        
Media/Content/Info | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 348,000 [1] 348,000 [2]        
Investments at Fair Value 0 0        
Media/Content/Info | Zoom Media Group, Inc. | Warrant Investment | Preferred Series A            
Investment Holdings [Line Items]            
Investment cost 348,000 [1] 348,000 [2]        
Investments at Fair Value $ 0 $ 0        
Investment, Acquisition Date Dec. 21, 2012 [5] Dec. 21, 2012 [6]        
Shares | shares 1,204 1,204 1,204 1,204    
Electronics & Computer Hardware            
Investment Holdings [Line Items]            
Investments at Fair Value $ 2,498,000 $ 1,040,000        
Electronics & Computer Hardware | Equity            
Investment Holdings [Line Items]            
Investment cost [1] 1,500,000          
Investments at Fair Value 1,034,000          
Electronics & Computer Hardware | Warrant Investment            
Investment Holdings [Line Items]            
Investment cost 692,000 [1] 658,000 [2]        
Investments at Fair Value 1,464,000 1,040,000        
Electronics & Computer Hardware | Locus Robotics Corporation | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost [1] 34,000          
Investments at Fair Value $ 27,000          
Investment, Acquisition Date [5] Jun. 21, 2022          
Shares | shares 8,511   8,511      
Electronics & Computer Hardware | Skydio, Inc. | Equity | Preferred Series E            
Investment Holdings [Line Items]            
Investment cost [1] $ 1,500,000          
Investments at Fair Value $ 1,034,000          
Investment, Acquisition Date [5] Mar. 08, 2022          
Shares | shares 248,900   248,900      
Electronics & Computer Hardware | Skydio, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 557,000 [1] 557,000 [2]        
Investments at Fair Value $ 1,153,000 $ 422,000        
Investment, Acquisition Date Nov. 08, 2021 [5] Nov. 08, 2021 [6]        
Shares | shares 622,255 124,451 622,255 124,451    
Electronics & Computer Hardware | 908 Devices, Inc. | Warrant Investment | Common Stock            
Investment Holdings [Line Items]            
Investment cost $ 101,000 [1],[5] $ 101,000 [2],[6]        
Investments at Fair Value $ 284,000 [5] $ 618,000 [6]        
Investment, Acquisition Date Mar. 15, 2017 [5] Mar. 15, 2017 [6]        
Shares | shares 49,078 [5] 49,078 [6] 49,078 [5] 49,078 [6]    
Investment, Affiliated Issuer, Controlled [Member]            
Investment Holdings [Line Items]            
Investment cost $ 87,249,000 $ 84,039,000        
Investments at Fair Value 80,325,000 [40] $ 73,504,000 [41]     $ 65,835,000 $ 57,400,000
Investment, Affiliated Issuer, Controlled [Member] | Gibraltar Business Capital, LLC            
Investment Holdings [Line Items]            
Investments at Fair Value [42] 37,662,000       40,737,000  
Investment, Affiliated Issuer, Controlled [Member] | Hercules Adviser LLC            
Investment Holdings [Line Items]            
Investments at Fair Value [42] 33,945,000       16,804,000  
Investment, Affiliated Issuer, Controlled [Member] | Tectura Corporation            
Investment Holdings [Line Items]            
Investments at Fair Value [42] 8,318,000       8,294,000  
Investment, Affiliated Issuer, Controlled [Member] | Coronado Aesthetics, LLC            
Investment Holdings [Line Items]            
Investments at Fair Value [42] 400,000          
Investment, Affiliated Issuer, Controlled [Member] | Sustainable And Renewable Technology | Senior Secured Tranche A [Member] | Pineapple Energy LLC            
Investment Holdings [Line Items]            
Investment, Interest Rate, Paid in Kind   10.00%   10.00%    
Investment, Affiliated Issuer, Controlled [Member] | Sustainable And Renewable Technology | Senior Secured Tranche B [Member] | Pineapple Energy LLC            
Investment Holdings [Line Items]            
Investment, Interest Rate, Paid in Cash   10.00%   10.00%    
Principal Amount   $ 280,000        
Investment, Affiliated Issuer, Noncontrolled [Member]            
Investment Holdings [Line Items]            
Investment cost 0 13,547,000        
Investments at Fair Value 0 9,458,000 [41]     9,712,000 8,340,000
Investment, Affiliated Issuer, Noncontrolled [Member] | Pineapple Energy LLC            
Investment Holdings [Line Items]            
Investment cost   12,547,000        
Investments at Fair Value 0 [42],[43] 8,338,000 [41]     8,469,000 [42]  
Investment, Affiliated Issuer, Noncontrolled [Member] | Black Crow AI, Inc. affiliates            
Investment Holdings [Line Items]            
Investments at Fair Value [42] 0 [43]       1,243,000  
Investment, Affiliated Issuer, Noncontrolled [Member] | Sustainable And Renewable Technology | Senior Secured Tranche A [Member] | Pineapple Energy LLC            
Investment Holdings [Line Items]            
Principal Amount   7,500,000        
Investment cost   7,500,000        
Investments at Fair Value [41]   7,500,000        
Investment, Affiliated Issuer, Noncontrolled [Member] | Sustainable And Renewable Technology | Senior Secured Tranche B [Member] | Pineapple Energy LLC            
Investment Holdings [Line Items]            
Investment cost   280,000        
Investments at Fair Value [41]   247,000        
Investment, Affiliated Issuer [Member]            
Investment Holdings [Line Items]            
Investment cost 87,249,000 97,586,000        
Investments at Fair Value $ 80,325,000 [40] $ 82,962,000 [41]     $ 75,547,000 $ 65,740,000
[1] Gross unrealized appreciation, gross unrealized depreciation, and net unrealized depreciation for federal income tax purposes totaled $68.4 million, $110.0 million and $41.6 million, respectively. The tax cost of investments is $2.9 billion.
[2] Gross unrealized appreciation, gross unrealized depreciation, and net unrealized depreciation for federal income tax purposes totaled $121.0 million, $75.7 million, and $45.3 million, respectively. The tax cost of investments is $2.4 billion.
[3] Value as a percent of net assets. All amounts are stated in U.S. Dollars unless otherwise noted. The Company uses the Standard Industrial Code for classifying the industry grouping of its portfolio companies
[4] Value as a percent of net assets. All amounts are stated in U.S. Dollars unless otherwise noted. The Company uses the Standard Industrial Code for classifying the industry grouping of its portfolio companies.
[5] Except for warrants in 27 publicly traded companies and common stock in 42 publicly traded companies, all investments are restricted as of September 30, 2022 and were valued at fair value using Level 3 significant unobservable inputs as determined in good faith by the Company’s valuation committee (the “Valuation Committee”) and approved by the board of directors (the “Board”).
[6] Except for warrants in 26 publicly traded companies and common stock in 36 publicly traded companies, all investments are restricted as of December 31, 2021 and were valued at fair value using Level 3 significant unobservable inputs as determined in good faith by the Company’s Board.
[7] Interest rate PRIME represents 6.25% as of September 30, 2022. 1-month LIBOR, 3-month LIBOR and 6-month LIBOR represent 3.1427%, 3.7547%, and 4.2320%, respectively, as of September 30, 2022.
[8] Denotes second lien senior secured debt.
[9] Denotes that all or a portion of the debt investment principal includes accumulated PIK interest and is net of repayments.
[10] Denotes that there is an unfunded contractual commitment available at the request of this portfolio company as of September 30, 2022 (Refer to “Note 11 - Commitments and Contingencies”).
[11] Interest rate PRIME represents 3.25% as of December 31, 2021. 1-month LIBOR, 3-month LIBOR, and 6-month LIBOR represent, 0.14%, 0.24%, and 0.26%, respectively, as of December 31, 2021.
[12] Denotes that all or a portion of the debt investment is pledged as collateral under the SMBC Facility (as defined in “Note 5 — Debt”).
[13] Denotes unitranche debt with first lien “last-out” senior secured position and security interest in all assets of the portfolio company whereby the “last-out” portion will be subordinated to the “first-out” portion in a liquidation, sale or other disposition.
[14] Denotes that all or a portion of the debt investment is pledged as collateral under the SMBC Facility (as defined in “Note 5 — Debt”).
[15] Denotes that there is an unfunded contractual commitment available at the request of this portfolio company as of December 31, 2021. Refer to “Note 11 — Commitments and Contingencies”.
[16] Denotes unitranche debt with first lien “last-out” senior secured position and security interest in all assets of the portfolio company whereby the “last-out” portion will be subordinated to the “first-out” portion in a liquidation, sale or other disposition.
[17] Denotes that all or a portion of the debt investment secures the 2031 Asset-Backed Notes (as defined in “Note 5 — Debt”).
[18] Denotes that all or a portion of the investment is pledged as collateral under the MUFG Bank Facility (as defined in “Note 5 — Debt”).
[19] Denotes that the fair value of the Company’s total investments in this portfolio company represent greater than 5% of the Company’s total net assets as of September 30, 2022.
[20] Denotes that all or a portion of the debt investment principal includes accumulated PIK interest and is net of repayments.
[21] Denotes that the fair value of the Company’s total investments in this portfolio company represent greater than 5% of the Company’s total net assets as of December 31, 2021.
[22] Denotes all or a portion of the public equity or warrant investment was acquired in a transaction exempt from registration under the Securities Act of 1933 (“Securities Act”) and may be deemed to be “restricted securities” under the Securities Act.
[23] Denotes second lien senior secured debt.
[24] Control investment as defined under the 1940 Act in which Hercules owns at least 25% of the company’s voting securities or has greater than 50% representation on its board.
[25] Control investment as defined under the 1940 Act in which Hercules owns at least 25% of the company’s voting securities or has greater than 50% representation on its board.
[26] Denotes that all or a portion of the debt investment is convertible debt.
[27] Indicates assets that the Company deems not “qualifying assets” under section 55(a) of 1940 Act. Qualifying assets must represent at least 70% of the Company’s total assets at the time of acquisition of any additional non-qualifying assets.
[28] Non-U.S. company or the company’s principal place of business is outside the United States.
[29] Indicates assets that the Company deems not “qualifying assets” under section 55(a) of 1940 Act. Qualifying assets must represent at least 70% of the Company’s total assets at the time of acquisition of any additional non-qualifying assets.
[30] Non-U.S. company or the company’s principal place of business is outside the United States.
[31] Denotes that all or a portion of the investment in this portfolio company is held by Hercules Capital IV, L.P., the Company’s wholly owned small business investment company.
[32] Denotes that all or a portion of the investment in this portfolio company is held by HC IV, the Company’s wholly owned SBIC subsidiary.
[33] Denotes that all or a portion of the investment is pledged as collateral under the Union Bank Facility (as defined in “Note 5 — Debt”).
[34] Denotes all or a portion of the public equity or warrant investment was acquired in a transaction exempt from registration under the Securities Act of 1933 (“Securities Act”) and may be deemed to be “restricted securities” under the Securities Act.
[35] Affiliate investment as defined under the 1940 Act in which Hercules owns at least 5% but generally less than 25% of the company’s voting securities.
[36] Denotes investment in a non-voting security in the form of a promissory note. The terms of the notes provide the Company with a lien on the issuers' shares of Common Stock for Black Crow AI, Inc., subject to release upon repayment of the outstanding balance of the notes. As of September 30, 2022, the Black Crow AI, Inc. affiliates promissory notes had an outstanding balance of $3.0 million.
[37] Debt is on non-accrual status as of December 31, 2021, and is therefore considered non-income producing. Note that only the PIK portion is on non-accrual for the Company’s debt investment in Tectura Corporation and Pineapple Energy LLC.
[38] Debt is on non-accrual status as of September 30, 2022, and is therefore considered non-income producing. Note that as of September 30, 2022, only the PIK, or payment-in-kind, portion is on non-accrual for the Company’s debt investment in Tectura Corporation.
[39] Denotes that all or a portion of the debt investment is convertible debt.
[40] All of the Company’s control and affiliate investments are Level 3 investments valued using significant unobservable inputs.
[41] All of the Company’s control and affiliate investments are Level 3 investments valued using significant unobservable inputs.
[42] In accordance with Rules 3-09, 4-08(g), and Rule 10-01(b)(1) of Regulation S-X, (“Rule 3-09”, “Rule 4-08(g)”, and “Rule 10-01(b)(1)”, respectively), the Company must determine if its unconsolidated subsidiaries are considered “significant subsidiaries”. As of September 30, 2022 and September 30, 2021, there were no unconsolidated subsidiaries that are considered “significant subsidiaries”.
[43] As of September 30, 2022, Black Crow AI, Inc. and Pineapple Energy LLC are no longer affiliates as defined under the 1940 Act.