Investments - Narrative (Details) $ in Millions	Mar. 31, 2026 USD ($) security	Dec. 31, 2025 USD ($) security
Debt Securities, Available-for-Sale [Line Items]
Number of securities \| security	542	215
Number of positions \| security	1,665	1,624
Debt securities, available-for-sale, continuous unrealized loss position, largest single amount	$ 0.2	$ 0.1
Fixed income funds	75.5	63.4
Unfunded investment commitments	$ 0.0	$ 12.2
Percentage of total net asset value of hedge fund	1.00%	1.00%
Private Credit Funds
Debt Securities, Available-for-Sale [Line Items]
Unfunded investment commitments	$ 108.1	$ 108.1
Minimum
Debt Securities, Available-for-Sale [Line Items]
Percentage of total net asset value of hedge fund	88.00%	94.00%
Maximum
Debt Securities, Available-for-Sale [Line Items]
Percentage of total net asset value of hedge fund	12.00%	6.00%

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Debt Securities, Available-for-Sale, Number of Positions

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Percentage of Total Net Asset Value Of Hedge Fund

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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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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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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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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