Debt - Narrative (Details)

v3.25.4

Debt - Narrative (Details) $ / shares in Units, $ in Thousands									12 Months Ended
		Jun. 23, 2025 USD ($)	Jun. 03, 2025 USD ($)	Mar. 10, 2025 USD ($)	Feb. 05, 2025 USD ($)	Jul. 16, 2024 USD ($)	Jul. 09, 2024 USD ($)	Oct. 27, 2020 USD ($)	Dec. 31, 2025 USD ($) creditFacility $ / shares	Dec. 31, 2024 USD ($) creditFacility	Dec. 31, 2023 USD ($)	Jun. 16, 2025 USD ($)	Jun. 10, 2025 USD ($)	Jun. 09, 2025 USD ($)	Jun. 23, 2022 USD ($)	Jun. 22, 2022 USD ($)	Jan. 20, 2022 USD ($)	Sep. 16, 2021 USD ($)	Mar. 04, 2021 USD ($)	Nov. 04, 2020 USD ($)	Jun. 03, 2020 USD ($)	Feb. 05, 2020 USD ($)	Jul. 16, 2019 USD ($)	Sep. 24, 2018 USD ($)
Debt Instrument [Line Items]
Total Available									$ 2,782,136	$ 2,329,475
Repayment of debt									1,484,839	1,118,525	$ 683,000
Restricted cash									2,467	3,297	17,114
Loss on extinguishment of debt									$ 184	$ 171	$ 0
Number of available credit facilities | creditFacility									2	2
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit interest rate									6.14%	7.63%
Debt average amount outstanding									$ 328,300	$ 338,000
MUFG Bank Facility
Debt Instrument [Line Items]
Line of credit facility, description									funded by existing or additional lenders and with the agreement of MUFG Bank and subject to other customary conditions.
Interest rate plus applicable margin adjustment									2.75%
Line of credit facility, termination date									Jan. 13, 2026
SMBC Facility
Debt Instrument [Line Items]
Maximum borrowing capacity									$ 300,000
Line of credit facility, termination date									Nov. 26, 2029
Line of credit facility, unused capacity, commitment fee percentage									0.375%
SMBC Facility | Term Loan
Debt Instrument [Line Items]
Total Available									$ 25,000
Interest rate plus applicable margin adjustment									2.00%
SMBC Facility | Maximum
Debt Instrument [Line Items]
Interest rate plus applicable margin adjustment									2.00%
SMBC Facility | Minimum
Debt Instrument [Line Items]
Interest rate plus applicable margin adjustment									1.00%
VIE
Debt Instrument [Line Items]
Restricted cash									$ 2,467	3,297
SBA Debentures
Debt Instrument [Line Items]
Maximum borrowing capacity									350,000	350,000
Total Available	[1]								$ 350,000	350,000
SBA Debentures | SBIC V
Debt Instrument [Line Items]
Debt instrument license description									HC IV and SBIC V each received their licenses to operate as an SBIC on October 27, 2020 and July 9, 2024, respectively, and each license has a 10 year term.
License term								10 years
Maximum borrowing capacity							$ 175,000		$ 175,000	175,000
Total Available									$ 175,000
SBA Debentures | HC IV
Debt Instrument [Line Items]
Debt instrument license description									HC IV and SBIC V each received their licenses to operate as an SBIC on October 27, 2020 and July 9, 2024, respectively, and each license has a 10 year term.
License term							10 years
Maximum borrowing capacity								$ 175,000	$ 175,000	175,000
Total Available									$ 175,000
March 2026 B Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									The March 2026 B Notes may be redeemed in whole or in part at any time or from time to time at the Company’s option plus a "make whole" premium, if applicable.
Total Available									$ 50,000	50,000									$ 50,000
Debt instrument, interest rate																			4.55%
Debt retired									Mar. 04, 2026
Debt instrument, payment terms, description									Interest on the March 2026 B Notes is due semiannually.
Debt instrument, collateral									The March 2026 B Notes are general unsecured obligations of the Company that rank pari passu with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
July 2024 Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									On July 16, 2019, the Company issued $105.0 million in aggregate principal amount of 4.770% interest-bearing unsecured notes due on July 16, 2024 (the “July 2024 Notes”), unless repurchased in accordance with their terms, to qualified institutional investors in a private placement notes offering.
Total Available																							$ 105,000
Debt instrument, interest rate																							4.77%
Debt retired									Jul. 16, 2024
Debt instrument, payment terms, description									Interest on the July 2024 Notes was due semiannually.
Debt instrument, collateral									The July 2024 Notes were the general unsecured obligations of the Company that ranked pari passu with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
Repayment of debt						$ 105,000
Repayment of accrued interest						$ 2,500
February 2025 Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									On February 5, 2020, the Company issued $50.0 million in aggregate principal amount of 4.280% interest-bearing unsecured notes due February 5, 2025 (the “February 2025 Notes”), unless repurchased in accordance with their terms, to qualified institutional investors in a private placement notes offering.
Total Available									$ 0	50,000												$ 50,000
Debt instrument, interest rate																						4.28%
Debt retired									Feb. 05, 2025
Debt instrument, payment terms, description									Interest on the February 2025 Notes was due semiannually.
Debt instrument, collateral									The February 2025 Notes were the general unsecured obligations of the Company that ranked pari passu with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
Repayment of debt					$ 50,000
Repayment of accrued interest					$ 1,100
June 2025 Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									On June 3, 2020, the Company issued $70.0 million in aggregate principal amount of 4.310% interest-bearing unsecured notes due June 3, 2025 (the “June 2025 Notes”), unless repurchased in accordance with their terms, to qualified institutional investors in a private placement notes offering.
Total Available									$ 0	70,000											$ 70,000
Debt instrument, interest rate																					4.31%
Debt retired									Jun. 03, 2025
Debt instrument, payment terms, description									Interest on the June 2025 Notes was due semiannually.
Debt instrument, collateral									The June 2025 Notes were the general unsecured obligations of the Company that ranked pari passu with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
Repayment of debt			$ 70,000
Repayment of accrued interest			$ 1,500
June 2025 3-Year Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									On June 23, 2022, the Company issued $50.0 million in aggregate principal amount of 6.000% interest-bearing unsecured notes due June 23, 2025 (the “June 2025 3-Year Notes”), unless repurchased in accordance with their terms, to qualified institutional investors in a private placement notes offering.
Total Available									$ 0	50,000					$ 50,000
Debt instrument, interest rate															6.00%
Debt retired									Jun. 23, 2025
Debt instrument, payment terms, description									Interest on the June 2025 3-Year Notes was due semiannually.
Debt instrument, collateral									The June 2025 3-Year Notes were the general unsecured obligations of the Company that ranked pari passu with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
Repayment of debt		$ 50,000
Repayment of accrued interest		$ 1,500
March 2026 A Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									The March 2026 A Notes may be redeemed in whole or in part at any time or from time to time at the Company’s option plus a "make whole" premium, if applicable.
Total Available									$ 50,000	50,000										$ 50,000
Debt instrument, interest rate																				4.50%
Debt retired									Mar. 04, 2026
Debt instrument, payment terms, description									Interest on the March 2026 A Notes is due semiannually.
Debt instrument, collateral									The March 2026 A Notes are general unsecured obligations of the Company that rank pari passu with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
September 2026 Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									The Company may redeem some or all of the September 2026 Notes at any time, or from time to time, at the redemption price set forth under the terms of the Seventh Supplemental Indenture.
Total Available									$ 325,000	325,000								$ 325,000
Debt instrument, interest rate																		2.625%
Debt retired									Sep. 16, 2026
Debt instrument, payment terms, description									Interest on the September 2026 Notes is payable semiannually in arrears on March 16 and September 16 of each year.
Debt instrument, collateral									The September 2026 Notes are general unsecured obligations and rank pari passu, or equally in right of payment, with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
January 2027 Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									The Company may redeem some or all of the January 2027 Notes at any time, or from time to time, at the redemption price set forth under the terms of the Eighth Supplemental Indenture.
Total Available									$ 350,000	350,000							$ 350,000
Debt instrument, interest rate																	3.375%
Debt retired									Jan. 20, 2027
Debt instrument, payment terms, description									Interest on the January 2027 Notes is payable semiannually in arrears on January 20 and July 20 of each year.
Debt instrument, collateral									The January 2027 Notes are general unsecured obligations and rank pari passu, or equally in right of payment, with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
2028 Convertible Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									On March 10, 2025, the Company issued $287.5 million in aggregate principal amount of 4.750% interest-bearing convertible unsecured notes due on September 1, 2028 (the “2028 Convertible Notes”), unless previously converted or caused to repurchase the notes in accordance with their terms by the holders of the 2028 Convertible Notes. The Company may not redeem the 2028 Convertible Notes at its option prior to maturity.
Total Available				$ 287,500					$ 287,500	0
Debt instrument, interest rate				4.75%
Debt retired									Sep. 01, 2028
Debt instrument, payment terms, description									Interest on the 2028 Convertible Notes is due semiannually.
Debt instrument, collateral									The 2028 Convertible Notes are unsecured obligations of the Company and rank pari passu, or equally in right of payment, with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
Debt instrument, convertible, conversion price | $ / shares									$ 21.48
Debt instrument, convertible, conversion ratio				0.0465631
June 2030 Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									The Company may redeem some or all of the June 2030 Notes at any time, or from time to time, at the redemption price set forth under the terms of the Ninth Supplemental Indenture.
Total Available									$ 350,000	0		$ 350,000
Debt instrument, interest rate												6.00%
Debt retired									Jun. 16, 2030
Debt instrument, payment terms, description									Interest on the June 2030 Notes is payable semiannually in arrears on June 16 and December 16 of each year, commencing December 16, 2025.
Debt instrument, collateral									The June 2030 Notes are general unsecured obligations and rank pari passu, or equally in right of payment, with all outstanding and future unsecured unsubordinated indebtedness issued by the Company.
2031 Asset-Backed Notes(2)
Debt Instrument [Line Items]
Total Available									$ 64,636	119,475						$ 150,000
Debt instrument, interest rate																4.95%
Debt retired									Jul. 20, 2031
Debt instrument, payment terms, description									Interest on the 2031 Asset-Backed Notes will be paid, to the extent of funds available.
Repayment of debt									$ 54,800	30,500
Loss on extinguishment of debt									184	171
2031 Asset-Backed Notes(2) | VIE
Debt Instrument [Line Items]
Restricted cash									$ 2,500	3,300
2033 Notes
Debt Instrument [Line Items]
Debt instrument, redemption, description									The Company may redeem some or all of the 2033 Notes at any time, or from time to time, at the redemption price set forth under the terms of the Sixth Supplemental Indenture after October 30, 2023.
Total Available									$ 40,000	40,000														$ 40,000
Debt instrument, interest rate																								6.25%
Debt retired									Oct. 30, 2033
Debt instrument, payment terms, description									Interest on the 2033 Notes is payable quarterly in arrears on January 30, April 30, July 30, and October 30 of each year.
Debt instrument, collateral									The 2033 Notes trade on the NYSE under the symbol “HCXY.” The 2033 Notes are general unsecured obligations and rank pari passu, or equally in right of payment, with all outstanding and future unsecured unsubordinated indebtedness issued by the Company
MUFG Bank Facility
Debt Instrument [Line Items]
Total Available									$ 440,000	400,000
MUFG Bank Facility | Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity													$ 440,000	$ 400,000
Accordion feature, increase limit									$ 600,000
Line of credit facility, covenant terms									these covenants require the Company to maintain certain financial ratios, including a minimum interest coverage ratio and a minimum tangible net worth with respect to Hercules Funding IV.
MUFG Bank Facility | Line of Credit | Minimum
Debt Instrument [Line Items]
Debt instrument, additional basis spread on variable rate									2.50%
SMBC Facility
Debt Instrument [Line Items]
Total Available	[2],[3]								$ 475,000	475,000
SMBC Facility | Term Loan
Debt Instrument [Line Items]
Total Available									25,000	25,000
SMBC Facility | SMBC Facility
Debt Instrument [Line Items]
Line of credit facility, termination date					Feb. 05, 2028
SMBC Facility | SMBC LC Facility
Debt Instrument [Line Items]
Maximum borrowing capacity					$ 175,000				$ 175,000	$ 175,000
Line of credit facility, description									Availability under the revolving SMBC Facility will terminate on November 24, 2028, and the outstanding loans under the SMBC Facility will mature on November 26, 2029
Accordion feature, increase limit					$ 400,000				$ 500,000
[1] As of December 31, 2025 and December 31, 2024, the total available debt under the SBA Debentures was $350.0 million, of which $175.0 million was available to HC IV and $175.0 million was available to SBIC V. [2] In November 2024, the Company amended its SMBC Facility and converted a portion of the existing revolver facility into a term loan facility in connection therewith. As of December 31, 2025, the term loan portion of the SMBC Facility for total available, outstanding principal, and carrying value was $25.0 million, $25.0 million, and $24.8 million, respectively. As of December 31, 2024, the term loan portion of the SMBC Facility for total available, outstanding principal, and carrying value was $25.0 million, $25.0 million, and $24.8 million, respectively. [3] “Total Available” includes $175.0 million of available commitment through the letter of credit facility as of December 31, 2025 and December 31, 2024.