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STATEMENT OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Statement of Comprehensive Income [Abstract] |  |  |
Income Tax Expense (Benefit), Change in Net Unrealized Gain on Securities | $ 200.4 | $ (226.6) | $ 300.6
Income Tax Expense (Benefit), Change in the Effect of Discount Rate Assumptions on the Liability for Future Policy and Contract Benefits | (66.2) | 488.9 | (256.5)
Income Tax Benefit, Change in Net Gain (Loss) on Derivatives | (3.1) | (51.5) | (17.0)
Income Tax Expense (Benefit), Change in Foreign Currency Translation Adjustment | 0.1 | 1.1 | 0.9
Income Tax Expense (Benefit), Change in Unrecognized Pension and Postretirement Benefit Costs | $ 35.6 | $ 12.0 | $ (2.7)

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