Fair Value - Summary of The Changes In Fair Value Of Level 3 Assets (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2025		Jun. 30, 2025		Dec. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Recurring Basis Unobservable Input Reconciliation Asset Gain Loss Statement Of Income Extensible List Not Disclosed [Flag]	us-gaap:EstimateOfFairValueFairValueDisclosureMember		us-gaap:EstimateOfFairValueFairValueDisclosureMember		us-gaap:EstimateOfFairValueFairValueDisclosureMember
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Opening balance	$ 275,318		$ 316,509		$ 420,518
Net realized gain	0		0		71
Net change in unrealized gain (loss)	(2,373)		(5,646)		(3,482)	[1]
Purchase of investment securities*	1,173	[2]	2,636	[3]	25,022
Proceeds from dispositions of investment securities	(31,631)		(71,012)		(125,620)
Transfers into Level 3	0		0		0
Transfers out of Level 3	0		0		0
Closing balance	242,487		242,487		316,509
Net change in unrealized gain (loss)	(2,238)		(4,871)		(3,306)
Bank Debt/Senior Secured Loans | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Opening balance	255,323		294,802		406,543
Net realized gain	0		0		71
Net change in unrealized gain (loss)	(1,465)		(2,255)		(1,454)	[1]
Purchase of investment securities*	537	[2]	1,229	[3]	15,144
Proceeds from dispositions of investment securities	(31,631)		(71,012)		(125,502)
Transfers into Level 3	0		0		0
Transfers out of Level 3	0		0		0
Closing balance	222,764		222,764		294,802
Net change in unrealized gain (loss)	(1,330)		(1,480)		(1,278)
Preferred Equity [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Opening balance	10,453		10,223		0
Net realized gain	0		0		0
Net change in unrealized gain (loss)	(38)		(76)		470	[1]
Purchase of investment securities*	273	[2]	541	[3]	9,753
Proceeds from dispositions of investment securities	0		0		0
Transfers into Level 3	0		0		0
Transfers out of Level 3	0		0		0
Closing balance	10,688		10,688		10,223
Net change in unrealized gain (loss)	(38)		76		470
Common Equity/Equity Interests/Warrants | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Opening balance	9,542		11,484		13,975
Net realized gain	0		0		0
Net change in unrealized gain (loss)	(870)		(3,315)		(2,498)	[1]
Purchase of investment securities*	363	[2]	866	[3]	125
Proceeds from dispositions of investment securities	0		0		(118)
Transfers into Level 3	0		0		0
Transfers out of Level 3	0		0		0
Closing balance	9,035		9,035		11,484
Net change in unrealized gain (loss)	$ (870)		$ (3,315)		$ (2,498)

[1] Includes PIK capitalization and accretion of discount.

[2] Includes PIK capitalization and accretion of discount.

[3] Includes PIK capitalization and accretion of discount.