Fair Value Measurements - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
SBIC investments	$ 122,602,000	$ 121,072,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0
Borrowings - Credit-Link Notes	112,500,000
Other Borrowings, Fair Value Disclosure	111,250,000	113,634,000
Interest Expense, Operating	155,825,000	165,586,000	$ 174,291,000
Credit-linked notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Secured debt	2,100,000,000
Other Borrowings, Fair Value Disclosure	111,250,000	$ 113,634,000
Interest Expense, Operating	4,100,000		$ 4,500,000
Warrant
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	$ 1,100,000