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Face (par) amount of debt instrument at time of issuance.

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Period remaining for expected liquidation by investee of underlying asset of investment measured at net asset value (NAV) per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investment calculated using unit, membership interest, other equity or ownership interest, and alternative investment.

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The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

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Fair value of financial and nonfinancial obligations.

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Fair Value Measurement (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
Fair Value Measurement (Narrative) (Details) - USD ($)	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Percentage of portfolio of unadjusted fair values obtained	98.80%
Three private equity funds using NAV	$ 75,900,000
Transfers between Levels 1, 2, and 3 of the fair value hierarchy	0	$ 0
Fair Value, Measurements, Nonrecurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value disclosure	0
Liabilities, fair value disclosure	0
Unsecured Notes Two \| Revolving Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Drawn down amount under credit facility	$ 200,000,000		$ 200,000,000
Minimum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, liquidating investment, remaining period	1 year
Maximum
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, liquidating investment, remaining period	7 years
Venture Capital Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
One private equity fund using NAV	$ 6,400,000
Private Equity Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unfunded commitments to VIEs	4,000,000		4,000,000
Level 2 \| Unsecured notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unsecured notes	375,000,000		375,000,000
Level 2 \| Commercial Mortgage Back Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, trading, and equity securities, FV-NI	$ 16,400,000		$ 11,200,000