Transactions with Controlled Companies - Credit Central Loan Company, LLC (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2023
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income	$ 671,109	$ 770,312	$ 760,785
Structuring Fee	12,348	27,666	18,131
Total Other Income	28,949	79,397	83,023
Interest Receivable	$ 25,144	$ 26,936
Credit Central Loan Company, LLC \| Credit Central Holdings of Delaware, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest	99.80%	99.80%
Credit Central, LLC \| Credit Central Loan Company, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest	100.00%	100.00%
Credit Central South, LLC \| Credit Central Loan Company, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest	100.00%	100.00%
Credit Central of Texas, LLC \| Credit Central Loan Company, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest	100.00%	100.00%
Credit Central of Tennessee, LLC \| Credit Central Loan Company, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest	100.00%	100.00%
Reportable Legal Entities \| Subsidiaries \| Credit Central Loan Company, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income	$ 8,711	$ 8,207	8,040
Structuring Fee	0	0	123
Total Other Income	0	0	123
Additions	0	0	6,200
Accreted Original Issue Discount	0	1,105	824
Interest Income Capitalized as PIK	7,949	4,882	7,237
Interest Receivable	26	0
Other Receivables	11	0
Reportable Legal Entities \| Subsidiaries \| Credit Central Loan Company, LLC \| Prospect Administration
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Managerial Assistance	700	700	700
Reimbursement of Legal, Tax, etc	$ 0	$ 6	$ 69
Reportable Legal Entities \| Subsidiaries \| Credit Central Holdings of Delaware, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest	100.00%	100.00%

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