Investments - Schedule of Net Investment Gains (Losses) (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Debt securities, available for sale | ||||
| Gross realized gains | $ 2.2 | $ 10.3 | $ 17.4 | $ 20.4 |
| Gross realized losses | (12.1) | (1.2) | (18.5) | (15.7) |
| Net realized gains (losses) on Debt securities, available for sale | (9.9) | 9.1 | (1.1) | 4.7 |
| Debt securities, trading | ||||
| Net realized gains (losses) | (0.1) | 0.1 | (1.4) | (1.7) |
| Net unrealized gains (losses) | (2.0) | 1.4 | (2.2) | 5.2 |
| Other long-term investments | ||||
| Net realized gains (losses) | 23.8 | (4.9) | 82.7 | (7.2) |
| Net unrealized gains (losses) | (8.7) | 0.4 | (56.5) | 4.1 |
| Other | 0.2 | 0.1 | 1.1 | 1.5 |
| Total net investment gains (losses) | $ 3.3 | $ 6.2 | $ 22.6 | $ 6.6 |
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- Definition Gains (Losses) On Other Investments No definition available.
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- Definition Net Realized Or Unrealized Gain Loss On Other Long-Term Investments No definition available.
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- Definition Other Long-Term Investments, Net Realized Gains (Losses) No definition available.
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- Definition Other Long-Term Investments, Net Unrealized Gains (Losses) No definition available.
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- References No definition available.
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- Definition Amount of realized gain 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 realized gain (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
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- Definition Amount of realized 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 realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of realized and unrealized gain (loss) on investment. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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