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Four Private Equity Funds using NAV

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Percentage of unadjusted fair value obtained

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Fair value portion of asset recognized for present right to economic benefit.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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- Definition

Fair value of financial and nonfinancial obligations.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair Value Measurement (Narrative) (Details) - USD ($)	6 Months Ended
Fair Value Measurement (Narrative) (Details) - USD ($)	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Percentage of portfolio of unadjusted fair values obtained	98.60%
Four private equity funds using NAV	$ 86,000,000.0
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
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	6 years
Venture Capital Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
One private equity fund using NAV	$ 8,200,000
Private Equity Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unfunded commitments to VIEs	16,000,000		$ 4,000,000
Level 2 \| Commercial Mortgage Back Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities, trading, and equity securities, FV-NI	$ 15,900,000		$ 11,200,000