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Fair Value Measurements - Summary of Reconciliation of Beginning and Ending Balances for Fair Valued Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Realized gain (loss) on investment	Realized gain (loss) on investment
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Realized gain (loss) on investment	Realized gain (loss) on investment
Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Net change in unrealized appreciation (depreciation) on investments	$ 2,840	$ 793
Level 3 | Fair Value, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	957,649	860,019
Net realized gains (losses) on investments	1,743	58
Net change in unrealized appreciation (depreciation) on investments	1,222	709
Purchase of investments	145,861	51,521
Proceeds from sales and repayments of investments	(60,247)	(15,871)
Interest and dividend income paid-in-kind	2,049	637
Proceeds from loan origination fees	(1,131)	(537)
Accretion of loan origination fees	556	413
Accretion of original issue discount	116	113
Ending Balance	1,047,818	897,062
Subordinated Debt | Level 3 | Fair Value, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	135,173	101,456
Net change in unrealized appreciation (depreciation) on investments	(75)	(1,565)
Purchase of investments	12,500	2,182
Proceeds from sales and repayments of investments	(209)
Interest and dividend income paid-in-kind	1,102	314
Proceeds from loan origination fees	(156)	(25)
Accretion of loan origination fees	50	22
Accretion of original issue discount	2	2
Ending Balance	148,387	102,386
First Lien Debt | Level 3 | Fair Value, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	578,140	456,105
Net change in unrealized appreciation (depreciation) on investments	1,116	133
Purchase of investments	96,142	40,980
Proceeds from sales and repayments of investments	(41,963)	(15,699)
Interest and dividend income paid-in-kind	256	127
Proceeds from loan origination fees	(896)	(481)
Accretion of loan origination fees	478	366
Accretion of original issue discount	17	16
Ending Balance	633,290	481,547
Second Lien Debt | Level 3 | Fair Value, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	119,561	182,948
Net change in unrealized appreciation (depreciation) on investments	453	698
Purchase of investments	28,850	5,000
Proceeds from sales and repayments of investments	(14,852)
Interest and dividend income paid-in-kind	691	196
Proceeds from loan origination fees	(79)	(31)
Accretion of loan origination fees	28	25
Accretion of original issue discount	97	95
Ending Balance	134,749	188,931
Equity | Level 3 | Fair Value, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	120,007	117,431
Net realized gains (losses) on investments	1,743	58
Net change in unrealized appreciation (depreciation) on investments	(1,456)	1,165
Purchase of investments	8,369	3,359
Proceeds from sales and repayments of investments	(3,222)	(172)
Ending Balance	125,441	121,841
Warrant | Level 3 | Fair Value, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	4,768	2,079
Net change in unrealized appreciation (depreciation) on investments	1,184	278
Proceeds from sales and repayments of investments	(1)
Ending Balance	$ 5,951	$ 2,357

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Indicates line item in statement in which net income is reported that includes unrealized gain (loss) from asset measured at fair value using unobservable input (level 3) and still held.

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Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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