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Investments - Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains on securities | $ 3 | $ 14
Net of tax |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains (losses) on securities before impairments | 8 | 13
Impairment allowance on securities | (6) | (2)
Realized gains on securities | 2 | 11
Change in unrealized | 61 | 9
Total pretax |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains (losses) on securities before impairments | 10 | 16
Impairment allowance on securities | (7) | (2)
Realized gains on securities | 3 | 14
Change in unrealized | 76 | 11
Fixed maturities |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains (losses) on securities before impairments | 1 | (4)
Impairment allowance on fixed maturity securities | (7) | (2)
Realized gains on securities | (6) | (6)
Change in unrealized | 76 | 11
Equity securities |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains (losses) on securities before impairments | 9 | 20
Realized gains on securities | 9 | 20
Change in unrealized | 0 | 0
Mortgage loans and other investments |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains (losses) on securities before impairments | 0 | 0
Impairment allowance on mortgage loans and other investments | 0 | 0
Realized gains on securities | 0 | 0
Change in unrealized | 0 | 0
Total tax effects |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains (losses) on securities before impairments | (2) | (3)
Impairment allowance on securities | 1 | 0
Realized gains on securities | (1) | (3)
Change in unrealized | $ (15) | $ (2)

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- Definition Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments. + References No definition available. + Details
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