SHAREHOLDERS' EQUITY - SCHEDULE OF ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Equity [Abstract] | ||
| Net unrealized losses on investments having no allowance for credit losses | $ (791.5) | $ (661.6) |
| Unrealized losses on investments with an allowance for credit losses | (1,254.5) | (1,193.9) |
| Change in discount rates for liability for future policy benefits | 523.9 | 421.1 |
| Change in instrument-specific credit risk for market risk benefits | 0.8 | 0.9 |
| Deferred income tax assets | 338.5 | 318.5 |
| Accumulated other comprehensive loss | (1,182.8) | (1,115.0) |
| Amortized cost | 8.5 | 12.0 |
| Total fixed maturities, available for sale | $ 8.8 | $ 13.0 |
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- Definition Accumulated Other Comprehensive Income (Loss), Changed in instrument Specific Credit Risk For Market Risk Benefits No definition available.
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- Definition Accumulated Other Comprehensive Income (Loss), Changes in Discount Rate for Liability for Future Policy Benefit No definition available.
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- Definition Accumulated Other Comprehensive Income (Loss), Deferred Income Tax Liabilities No definition available.
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- Definition Accumulated Other Comprehensive Income (Loss), Net Unrealized Appreciation On Investments Having No Allowance For Credit Losses No definition available.
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- Definition Accumulated Other Comprehensive Income (Loss), Net Unrealized Appreciation On Investments With Allowance For Credit Losses No definition available.
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- Definition Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss, Fair Value Option No definition available.
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- Definition Debt Securities, Available-for-Sale, Excluding Accrued Interest, Fair Value Option No definition available.
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- Definition Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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