Investments at Fair Value - Summary of Investments at Fair Value (Details) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
		Jun. 30, 2024	Dec. 31, 2023
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	[1]	$ 3,304,563	$ 3,251,012
Fair Value		3,317,069	3,283,065
Net Unrealized Gain (Loss)		12,506	32,053
First-lien Debt Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	[1]	3,048,775	2,956,079
Fair Value		3,078,445	2,996,177
Net Unrealized Gain (Loss)		29,670	40,098
Second-lien Debt Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	[1]	52,535	51,423
Fair Value		27,993	35,975
Net Unrealized Gain (Loss)		(24,542)	(15,448)
Mezzanine Debt Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	[1]	41,067	38,022
Fair Value		43,488	39,471
Net Unrealized Gain (Loss)		2,421	1,449
Equity and Other Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	[1]	156,390	152,623
Fair Value		161,019	155,600
Net Unrealized Gain (Loss)		4,629	2,977
Structured Credit Investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	[1]	5,796	52,865
Fair Value		6,124	55,842
Net Unrealized Gain (Loss)		$ 328	$ 2,977

[1] The amortized cost represents the original cost adjusted for the amortization of discounts or premiums, as applicable, on debt investments using the effective interest method.