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Reduction of net asset value.

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Repayment proceeds of cash.

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Unfunded investment commitments.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Date the declared dividend will be paid, in YYYY-MM-DD format.

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A description of the principal activities of an investee accounted for under the equity method.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Subsequent Events - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions				1 Months Ended	12 Months Ended
	Aug. 06, 2026	Aug. 04, 2026	Jun. 17, 2026	Aug. 05, 2026	Dec. 31, 2025	Jun. 30, 2026	Jun. 23, 2026	Jun. 30, 2025
Subsequent Event [Line Items]
Amount Per Share						$ 0.34		$ 0.58
Cash							$ 400.0
Repayment proceeds of cash							$ 69.0
SBA Debentures
Subsequent Event [Line Items]
Repayments of debt			$ 108.7
Transaction Agreement \| BlackRock DLF-C 2026
Subsequent Event [Line Items]
Equity method investment ownership percentage					95.00%
Gross proceeds					$ 152.0
Subsequent Event
Subsequent Event [Line Items]
Investment additional repayments				$ 97.4
Subsequent Event \| Minimum
Subsequent Event [Line Items]
Unfunded investment commitments		$ 36.0
Subsequent Event \| Maximum
Subsequent Event [Line Items]
Unfunded investment commitments		$ 90.0
Subsequent Event \| O 2026 Q3 Dividends
Subsequent Event [Line Items]
Dividend payable record date	Sep. 16, 2026
Amount Per Share	$ 0.17
Dividend payable date	Sep. 30, 2026
Subsequent Event \| S 2026 Q3 Dividends
Subsequent Event [Line Items]
Dividend payable record date	Sep. 16, 2026
Amount Per Share	$ 0.17
Dividend payable date	Sep. 30, 2026
Subsequent Event \| BlackRock DLF-C 2026
Subsequent Event [Line Items]
Equity method investment, description		On August 4, 2026, the Company, through its wholly-owned subsidiary SVCP, entered into a definitive agreement (the “Transaction Agreement”) providing for the sale of 95% of the limited liability company interests in BlackRock DLF-C 2026, LLC (the “Continuation Vehicle”), to a group of investment funds and accounts managed by Pantheon Ventures (US) LP, and retained a 5% interest (the “Transaction”). The Transaction generated approximately $152 million in gross proceeds and, together with investment repayments received post June 30, 2026, is expected to reduce net leverage from 1.38x to 0.4x (with a further reduction to less than 0.3x following an already announced portfolio company paydown).1
Reduction of net asset value		$ 57.0
Per share of reduction of net asset value		$ 0.68
Subsequent Event \| Motive Technologies, Inc
Subsequent Event [Line Items]
Investment additional repayments				55.2
Subsequent Event \| Pico Quantitative Trading, LLC.
Subsequent Event [Line Items]
Investment additional repayments				$ 39.6
Subsequent Event \| Transaction Agreement \| BlackRock DLF-C 2026
Subsequent Event [Line Items]
Equity method investment ownership percentage		95.00%
Equity method investment ownership retained percentage		5.00%
Gross proceeds		$ 152.0