Fair Value Measurements (Details) - Schedule of Quantitative Information About Level 3 Fair Value Measurements of Our Investments - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 165,316	$ 146,675
Senior Secured First Lien Term Loans [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 69,943	$ 65,428
Valuation Methodology	Income Approach	Income Approach
Unobservable Input	Market Yield	Market Yield
Range (Weighted Average)	8.50% - 32.0% (13.78%)	8.50% - 24.00% (10.57%)
Impact to Valuation From An Increase In Input	Decrease
Senior Secured First Lien Term Loans One [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 751	$ 3,807
Valuation Methodology	Market Approach	Market Approach
Unobservable Input	Revenue Multiple	EBITDA Multiple
Range (Weighted Average)	0.3x - 0.3x (0.3x)	4.0x – 5.0x (4.5x)
Impact to Valuation From An Increase In Input	Increase
Senior Secured First Lien Term Loans Two [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 10,939	$ 4,152
Valuation Methodology	Market Approach	Market Approach
Unobservable Input	EBITDA Multiple	Revenue Multiple
Range (Weighted Average)	1.7x - 5.0x (3.1x)	0.2x – 0.3x (2.5x)
Impact to Valuation From An Increase In Input	Increase
Senior Secured First Lien Term Loans Three [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 866	$ 865
Valuation Methodology	Market Approach	Income Approach
Unobservable Input	LTM EBITDA Multiple	Market Spread
Range (Weighted Average)	5.8x - 6.8x (6.3x)	5.75% - 6.25% (6.00%)
Impact to Valuation From An Increase In Input	Increase
Equity Warrants [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 38,870	$ 47,138
Valuation Methodology	Cost Approach	Cost Approach
Unobservable Input	Collateral Value	Replacement Cost
Range (Weighted Average)	N/A	N/A
Impact to Valuation From An Increase In Input	N/A
Equity/Warrants Two [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 11,734	$ 9,951
Valuation Methodology	Market Approach	Market Approach
Unobservable Input	LTM Multiple	Market Yield
Range (Weighted Average)	5.8x – 6.8x (6.3x)	8.50% - 13.25% (12.75%)
Impact to Valuation From An Increase In Input	Increase
Equity/Warrants Three [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 22,007	$ 1,283
Valuation Methodology	Market Approach	Market Approach
Unobservable Input	EBITDA Multiple	Sum of the Parts/Estimated Proceeds
Range (Weighted Average)	1.8x – 36.8x (2.8x)	8.1x – 11.4x (9.8x)
Impact to Valuation From An Increase In Input	Increase
Equity/Warrants Four [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 10,000
Valuation Methodology	Recent Purchase
Unobservable Input	Purchase Price
Range (Weighted Average)	N/A – N/A (N/A)
Impact to Valuation From An Increase In Input	N/A
Equity/Warrants Five [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value	$ 206
Valuation Methodology	Income Approach
Unobservable Input	DLOM (Discount for lack of Marketability)
Range (Weighted Average)	3.0x – 3.2x (3.1x)
Impact to Valuation From An Increase In Input	Decrease
Senior Secured First Lien Term Loans Four [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value		$ 2,607
Valuation Methodology		Market Approach
Unobservable Input		EBITDA Multiple
Range (Weighted Average)		9.0x – 10.0x (9.5x)
Equity/Warrants One [Member]
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value		$ 11,444
Valuation Methodology		Market Approach
Unobservable Input		EBITDA Multiple
Range (Weighted Average)		2.0x – 21.0x (17.4x)

Fair Value Measurement Inputs and Valuation Techniques [Line Items]