Fair Value Measurement (Schedule of Investments in LLCs and Limited Partnerships) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2026 USD ($) fund	Dec. 31, 2025 USD ($)
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Fair Value	$ 214,423	$ 214,455
Private debt funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Number of limited partners in investment \| fund	1
Private debt funds \| Minimum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Liquidating investments remaining period	3 years
Private debt funds \| Maximum
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Liquidating investments remaining period	8 years
Non-public equity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Number of limited partners in investment \| fund	2
Liquidating investments remaining period	10 years
Credit funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Number of limited partners in investment \| fund	3
Number of limited partners to allow redemption by special consent \| fund	1
Investment redemption notice period	180 days
Number of LPs to allow redemption by special consent (in funds) \| fund	1
Strategy focused funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Number of limited partners not permitted for redemption \| fund	3
Number of limited partners, redemption allowed with prior notice \| fund	3
Investment in unconsolidated subsidiaries \| Private debt funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Contractual Commitments	$ 3,667
Fair Value	10,450	10,736
Investment in unconsolidated subsidiaries \| Non-public equity funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Contractual Commitments	33,105
Fair Value	89,443	92,164
Investment in unconsolidated subsidiaries \| Credit funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Contractual Commitments	70,485
Fair Value	54,914	54,373
Investment in unconsolidated subsidiaries \| Strategy focused funds
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Contractual Commitments	44,648
Fair Value	$ 59,616	$ 57,182

Fair Value, Investments, Entities that Calculate Net Asset Value, Investment Redemption, Notice Period, One Fund

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Number of Funds Focusing on Investing In North America Companies

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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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