Quarterly report [Sections 13 or 15(d)]

Investments - Schedule of Fair Value Portfolio by Industry Sector (Details)

v3.25.3
Investments - Schedule of Fair Value Portfolio by Industry Sector (Details) - USD ($)
$ in Thousands
 9 Months Ended 12 Months Ended
Sep. 30, 2025
Dec. 31, 2024
Schedule Of Investments [Line Items]    
Investments at Fair Value $ 4,306,154 $ 3,659,978
Industry Sector Concentration Risk | Total Industry Sectors    
Schedule Of Investments [Line Items]    
Investments at Fair Value 4,306,154 3,659,978
Industry Sector Concentration Risk | Software    
Schedule Of Investments [Line Items]    
Investments at Fair Value 1,519,464 1,081,100
Industry Sector Concentration Risk | Drug Discovery & Development    
Schedule Of Investments [Line Items]    
Investments at Fair Value 988,816 1,080,390
Industry Sector Concentration Risk | Healthcare Services, Other    
Schedule Of Investments [Line Items]    
Investments at Fair Value 833,492 610,184
Industry Sector Concentration Risk | Consumer & Business Services    
Schedule Of Investments [Line Items]    
Investments at Fair Value 433,323 372,641
Industry Sector Concentration Risk | Defense Technologies    
Schedule Of Investments [Line Items]    
Investments at Fair Value 140,622 0
Industry Sector Concentration Risk | Diversified Financial Services    
Schedule Of Investments [Line Items]    
Investments at Fair Value 104,221 113,491
Industry Sector Concentration Risk | Medical Devices & Equipment    
Schedule Of Investments [Line Items]    
Investments at Fair Value 76,389 74,962
Industry Sector Concentration Risk | Electronics & Computer Hardware    
Schedule Of Investments [Line Items]    
Investments at Fair Value 51,080 162,888
Industry Sector Concentration Risk | Space Technologies    
Schedule Of Investments [Line Items]    
Investments at Fair Value 34,019 45,700
Industry Sector Concentration Risk | Communications & Networking    
Schedule Of Investments [Line Items]    
Investments at Fair Value 27,535 27,700
Industry Sector Concentration Risk | Information Services    
Schedule Of Investments [Line Items]    
Investments at Fair Value 23,988 24,356
Industry Sector Concentration Risk | Biotechnology Tools    
Schedule Of Investments [Line Items]    
Investments at Fair Value 22,326 35,434
Industry Sector Concentration Risk | Sustainable and Renewable Technology    
Schedule Of Investments [Line Items]    
Investments at Fair Value 21,300 27,696
Industry Sector Concentration Risk | Manufacturing Technology    
Schedule Of Investments [Line Items]    
Investments at Fair Value 20,419 1,162
Industry Sector Concentration Risk | Consumer & Business Products    
Schedule Of Investments [Line Items]    
Investments at Fair Value 8,716 1,497
Industry Sector Concentration Risk | Semiconductors    
Schedule Of Investments [Line Items]    
Investments at Fair Value 339 704
Industry Sector Concentration Risk | Media/Content/Info    
Schedule Of Investments [Line Items]    
Investments at Fair Value 93 63
Industry Sector Concentration Risk | Drug Delivery    
Schedule Of Investments [Line Items]    
Investments at Fair Value $ 12 $ 10
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Total Industry Sectors    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 100.00% 100.00%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Software    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 35.30% 29.50%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Drug Discovery & Development    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 23.00% 29.50%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Healthcare Services, Other    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 19.30% 16.70%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Consumer & Business Services    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 10.10% 10.20%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Defense Technologies    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 3.30% 0.00%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Diversified Financial Services    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 2.40% 3.10%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Medical Devices & Equipment    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 1.80% 2.00%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Electronics & Computer Hardware    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 1.20% 4.50%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Space Technologies    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.80% 1.20%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Communications & Networking    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.60% 0.80%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Information Services    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.50% 0.70%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Biotechnology Tools    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.50% 1.00%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Sustainable and Renewable Technology    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.50% 0.80%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Manufacturing Technology    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.50% 0.00%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Consumer & Business Products    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.20% 0.00%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Semiconductors    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.00% 0.00%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Media/Content/Info    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.00% 0.00%
Industry Sector Concentration Risk | Industry Sector Investments Benchmark | Drug Delivery    
Schedule Of Investments [Line Items]    
Percentage of Total Portfolio 0.00% 0.00%