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Fair Value (Narrative) (Details) - USD ($)	Dec. 31, 2025	Dec. 31, 2024
Fair Value Measurements [Line Items]
Investments measured at net asset value based on an ownership interest in partners'	1.00%	1.00%
Level 3 [Member]
Fair Value Measurements [Line Items]
Investments measured at fair value using net asset value	$ 3,400,000	$ 3,900,000
Liabilities held	0	0
Valuation for equity security based on dealer quote	11,700,000
Investments Net Asset Value [Member]
Fair Value Measurements [Line Items]
Investments measured at fair value using net asset value	$ 64,100,000	$ 83,000,000
Investment, Type [Extensible Enumeration]	Partnership Interest [Member]	Partnership Interest [Member]

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Fair Value Measurements [Line Items]

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Percentage Of Investments Not Included In Fair Value Of Financial Instruments

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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