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Transactions with Controlled Companies - Credit Central Loan Company, LLC (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Mar. 31, 2023	Sep. 30, 2022	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Jun. 30, 2022
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income	$ 198,136		$ 142,489	$ 563,330	$ 430,933
Structuring Fee	145		10,149	9,875	38,963
Total Other Income	15,056		33,636	60,334	83,071
Interest Receivable	27,029			27,029		$ 12,925
Other Receivables	1,063			$ 1,063		745
Credit Central Holdings of Delaware, LLC \| Credit Central Loan Company, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest		99.00%		99.81%
Credit Central Loan Company, LLC \| Credit Central, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest				100.00%
Credit Central Loan Company, LLC \| Credit Central South, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest				100.00%
Credit Central Loan Company, LLC \| Credit Central of Texas, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest				100.00%
Credit Central Loan Company, LLC \| Credit Central of Tennessee, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest				100.00%
Reportable Legal Entities \| Subsidiaries \| Credit Central Holdings of Delaware, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest				100.00%
Reportable Legal Entities \| Subsidiaries \| Credit Central Loan Company, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income	2,065		3,781	$ 5,878	11,182
Structuring Fee	62		0	123	0
Total Other Income	62		0	123	0
Additions	3,080		0	6,200	0
Accreted Original Issue Discount	210		155	594	439
Interest Income Capitalized as PIK	2,457		3,007	5,303	6,564
Interest Receivable	21			21		42
Other Receivables	2			2		$ 7
Reportable Legal Entities \| Subsidiaries \| Credit Central Loan Company, LLC \| Prospect Administration
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Managerial Assistance	175		175	525	525
Reimbursement of Legal, Tax, etc	$ 12		$ 0	$ 69	$ 1