Investments - Consolidated Statements of Operations for PSLF (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Expenses:
Interest expense on notes to members	$ 9,729	$ 6,886
General and administrative expenses	266	250
Other general and administrative expenses	841	723
Net expenses	19,630	15,825
Net investment income	10,333	12,524
Realized and unrealized gain (loss) on investments:
Net realized gain (loss) on investments	(4,064)	27,742
PSLF
Investment income:
Interest	18,845	7,570
Other income	97	103
Total investment income	18,942	7,673
Expenses:
Interest expense on credit facility and asset-backed debt	7,815	1,609
Interest expense on notes to members	4,723	2,439
Administrative services expenses	727	293
General and administrative expenses	114	112
Net expenses	13,379	4,453
Net investment income	5,563	3,220
Realized and unrealized gain (loss) on investments:
Net realized gain (loss) on investments	(33)	(1)
Net change in unrealized appreciation (depreciation) on Investments	(3,922)	506
Net realized and unrealized gain (loss) from investments, Total	(3,955)	505
Net increase (decrease) in members' equity resulting from operations, Total	$ 1,608	$ 3,725