Transactions with Controlled Companies - Nationwide Loan Company LLC (Details) - USD ($) $ in Thousands		12 Months Ended
Jun. 20, 2025	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
Nationwide Loan Company LLC \| Members of Nationwide Management
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest		5.78%
Converted to equity	$ 29,091
Nationwide Loan Company LLC \| Nationwide Acceptance Holdings LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest		94.22%	94.48%
Reportable Legal Entities \| Subsidiaries \| Nationwide Acceptance Holdings LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income		$ 3,793	$ 5,111	4,306
Structuring Fee		0	147	0
Total Other Income		0	147	0
Additions		4,000	5,350	0
Interest Income Capitalized as PIK		2,484	4,622	2,337
Interest Receivable		3	501
Other Receivables		36	1
Reportable Legal Entities \| Subsidiaries \| Nationwide Acceptance Holdings LLC \| Prospect Administration
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Managerial Assistance		400	100	400
Reimbursement of Legal, Tax, etc		$ 115	$ 3	$ 0
Reportable Legal Entities \| Subsidiaries \| Nationwide Acceptance Holdings LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest		100.00%	100.00%

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