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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, 2024 | Mar. 31, 2023
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains (losses) on securities | $ 14 | $ (46)
Net of tax |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | 13 | (33)
Realized — impairments | (2) | (4)
Realized gains (losses) on securities | 11 | (37)
Change in unrealized | 9 | 84
Total pretax |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | 16 | (41)
Realized — impairments | (2) | (5)
Realized gains (losses) on securities | 14 | (46)
Change in unrealized | 11 | 107
Fixed maturities: |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | (4) | (23)
Realized — impairments | (2) | (5)
Realized gains (losses) on securities | (6) | (28)
Change in unrealized | 11 | 107
Equity securities |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | 20 | (18)
Realized — impairments | 0 | 0
Realized gains (losses) on securities | 20 | (18)
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 before impairments | 0 | 0
Realized — impairments | 0 | 0
Realized gains (losses) on securities | 0 | 0
Change in unrealized | 0 | 0
Tax effects |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | (3) | 8
Realized — impairments | 0 | 1
Realized gains (losses) on securities | (3) | 9
Change in unrealized | $ (2) | $ (23)

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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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- Definition Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI). + References No definition available. + Details
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- Definition Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 8A -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-8A + Details
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