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Transactions with Controlled Companies - Credit Central Loan Company, LLC (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2025	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income		$ 581,932	$ 671,109	$ 770,312
Interest Receivable		$ 17,350	25,144
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		$ 6,355	8,711	8,207
Additions		2,714	0	0
Accreted Original Issue Discount		0	0	1,105
Interest Income Capitalized as PIK		0	7,949	4,882
Interest Receivable		15	26
Other Receivables		79	11
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	$ 0	$ 6
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%