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Borrowings - SBA-guaranteed Debentures, Narrative (Details) $ in Thousands		3 Months Ended
	Feb. 28, 2025 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
Debt Instrument [Line Items]
SBA-guaranteed debentures outstanding		$ 262,500		$ 300,000
Repayment of SBA-guaranteed debentures		$ 37,500	$ 0
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		112,500		150,000
SBIC II
Debt Instrument [Line Items]
Regulatory capital		75,000		75,000
SBA-guaranteed debentures outstanding		$ 150,000		$ 150,000
SBA-guaranteed debentures
Debt Instrument [Line Items]
Term of debt		10 years
Repayment of SBA-guaranteed debentures	$ 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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