Transactions with Controlled Companies - QC Holdings TopCo, LLC (Details) - USD ($) $ in Thousands	12 Months Ended
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
Structuring Fee	9,000	12,348	27,666
Total Other Income	10,555	28,949	79,397
Interest Receivable	17,350	25,144
Subsidiaries \| Reportable Legal Entities \| QC Holdings TopCo, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income	13,767	37	0
Structuring Fee	0	2,319	0
Total Other Income	0	2,319	0
Additions	6,805	77,286	0
Interest Receivable	40	37
Other	(122)	(132)
Subsidiaries \| Reportable Legal Entities \| QC Holdings TopCo, LLC \| Prospect Administration
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Managerial Assistance	650	0	0
Reimbursement of Legal, Tax, etc	$ 269	$ 0	$ 0
QC Holdings TopCo, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest	95.40%	99.55%

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