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Amount of fees and commissions from banking, advisory, brokerage, and securities underwriting activities. Activities include, but are not limited to, underwriting securities, private placements of securities, investment advisory and management services, merger and acquisition services, sale and servicing of mutual funds, and other related consulting fees.

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Transactions with Controlled Companies - Belnick, LLC (Details) - USD ($) $ in Thousands			12 Months Ended
	May 23, 2025	May 22, 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
Belnick Holdings of Delaware, LLC \| Belnick, LLC (d/b/a The Ubique Group)
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest	100.00%		99.01%
Subsidiaries \| Reportable Legal Entities \| Belnick, LLC (d/b/a The Ubique Group)
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income			$ 2,748	0	0
Structuring Fee			33	0	0
Total Other Income			33	0	0
Additions			3,400	0	0
Interest Receivable			31	0
Other Receivables			(41)	0
Equity funding			3,400
Subsidiaries \| Reportable Legal Entities \| Belnick, LLC (d/b/a The Ubique Group) \| Prospect Administration
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Reimbursement of Legal, Tax, etc			8	0	0
Subsidiaries \| Reportable Legal Entities \| Belnick, LLC (d/b/a The Ubique Group) \| Prospect Administration LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Total Interest Income Capitalized as PIK			$ 2,740	$ 0	$ 0
Subsidiaries \| Reportable Legal Entities \| Belnick Holdings of Delaware, LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest		100.00%