Investments - Narratives (Details) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2026 USD ($) security	Dec. 31, 2025 USD ($) security
Investments
AFS securities with continuous loss position (security) \| security	370	313
AFS securities with continuous loss position for more than 12 months (security) \| security	191	207
Credit Loss \| Insurance Solutions
Investments
Off balance sheet credit risk	$ 0.1	$ 0.1
Corporate loans \| Line of Credit \| Asset Management
Investments
Off balance sheet credit risk	1.4	1.4
Corporate loans \| Line of Credit \| Insurance Solutions
Investments
Off balance sheet credit risk	5.9	4.3
Below Investment Grade
Investments
AFS, unrealized loss	4.6	4.0
Below Investment Grade \| Single Largest Investment
Investments
AFS, unrealized loss	$ 1.6	$ 1.2

Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
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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 continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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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.

+ References

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Section 45
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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