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Investment Company, Professional Fee Income

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Amount of fee income including, but not limited to, managerial assistance, servicing of investment, and origination and commitment fees.

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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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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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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Transactions with Controlled Companies - Nationwide Loan Company LLC (Details) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
	Jun. 20, 2025	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
Structuring Fee			9,000	12,348	27,666
Total Other Income			10,555	28,949	79,397
Interest Receivable			$ 17,350	25,144
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 Loan Company LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest		94.22%	94.22%
Reportable Legal Entities \| Subsidiaries \| Nationwide Loan Company LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income			$ 1,049	3,793	5,111
Structuring Fee			0	0	147
Total Other Income			0	0	147
Additions			0	4,000	5,350
Interest Income Capitalized as PIK			1,049	2,484	4,622
Interest Receivable			3	3
Other Receivables			55	36
Reportable Legal Entities \| Subsidiaries \| Nationwide Loan Company LLC \| Prospect Administration
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Managerial Assistance			400	400	100
Reimbursement of Legal, Tax, etc			$ 3	$ 115	$ 3
Reportable Legal Entities \| Subsidiaries \| Nationwide Loan Company LLC
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest		100.00%	100.00%