Investments - Net Investment Gains (Losses) by Transaction Type (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
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| Investments, Debt and Equity Securities [Abstract] | ||||
| Credit loss impairments | $ (0.9) | $ 0.9 | $ (0.9) | $ 0.0 |
| Intent-to-sell impairments | (2.2) | 0.0 | (2.2) | 0.0 |
| Total impairments | (3.1) | 0.9 | (3.1) | 0.0 |
| Sales and other, net | 2.0 | (3.2) | 4.1 | (3.3) |
| Change in fair value - equity securities | (0.7) | (2.1) | (1.9) | 0.5 |
| Change in fair value and gains (losses) realized on settlements - derivatives | (4.1) | (1.5) | (8.3) | (0.9) |
| Net investment gains (losses) | $ (5.9) | $ (5.9) | $ (9.2) | $ (3.7) |
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- Definition Impairments Of Investments No definition available.
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- Definition Other than Temporary Impairment Losses, Investments, Portion Recognized In Earnings, Change In Intent No definition available.
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- Definition Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of unrealized and realized gain (loss) on investment in debt and equity securities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of writeoff of allowance for credit 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/2003/role/disclosureRef
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- Definition Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of realized gain (loss) on investment. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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