v3.25.2

BORROWINGS - Schedule of Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Sep. 30, 2024
Debt Instrument [Line Items]
Credit Facility	$ 27,500		$ 27,500		$ 70,600
Significant Unobservable Inputs (Level 3) \| Fair Value, Recurring
Debt Instrument [Line Items]
Credit Facility	27,500		27,500		$ 70,600
Significant Unobservable Inputs (Level 3) \| Fair Value, Recurring \| Long-Term Debt
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance	25,149	$ 117,200	70,600	$ 47,800
Borrowings	63,500	45,200	212,000	179,500
Repayments	(61,100)	(96,600)	(255,100)	(161,500)
Net unrealized appreciation	(49)	0	0	0
Ending balance	$ 27,500	$ 65,800	$ 27,500	$ 65,800

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Unrealized Appreciation (Depreciation)

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sales of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

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GLADSTONE CAPITAL CORP 10-Q