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Borrowings - SBA-Guaranteed Debentures, Narrative (Details) $ in Thousands			9 Months Ended
	Aug. 29, 2025 USD ($)	Feb. 28, 2025 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Debt Instrument [Line Items]
Repayment of SBA-guaranteed debentures			$ 103,795	$ 0
SBA-guaranteed debentures outstanding			$ 196,205		$ 300,000
Upfront fees percentage			0.03435
Commitment fee percentage			0.0100
Issuance discount percentage			0.02435
SBIC I
Debt Instrument [Line Items]
Regulatory capital			$ 75,000		75,000
SBA-guaranteed debentures outstanding			46,205		150,000
SBIC II
Debt Instrument [Line Items]
Regulatory capital			75,000		75,000
SBA-guaranteed debentures outstanding			150,000		$ 150,000
SBIC III
Debt Instrument [Line Items]
Regulatory capital			$ 3,375
SBA-guaranteed debentures
Debt Instrument [Line Items]
Term of debt			10 years
Repayment of SBA-guaranteed debentures	$ 66,295	$ 37,500
Debt instrument, variable interest rate, type [Extensible Enumeration]			Federal Home Loan Bank Of Chicago's Fixed Regular Advance Rate ("Bank Advance Rate") [Member]
Interest rate margin			0.41%

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