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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, 2023 | Mar. 31, 2022
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized gains (losses) on securities | $ (46) | $ (15)
Net of tax |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | (33) | (14)
Realized — impairments | (4) | 2
Realized gains (losses) on securities | (37) | (12)
Change in unrealized | 84 | (245)
Total pretax |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | (41) | (17)
Realized — impairments | (5) | 2
Realized gains (losses) on securities | (46) | (15)
Change in unrealized | 107 | (311)
Fixed maturities |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | (23) | (4)
Realized — impairments | (5) | 2
Realized gains (losses) on securities | (28) | (2)
Change in unrealized | 107 | (311)
Equity securities |  |
Realized gains (losses) and changes in unrealized appreciation (depreciation) related to fixed maturity and equity security investments |  |
Realized before impairments | (18) | (13)
Realized — impairments | 0 | 0
Realized gains (losses) on securities | (18) | (13)
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 | 8 | 3
Realized — impairments | 1 | 0
Realized gains (losses) on securities | 9 | 3
Change in unrealized | $ (23) | $ 66

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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 realized gain (loss) on investment in marketable security, excluding 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://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 8A -URI https://asc.fasb.org/extlink&oid=124260329&loc=SL6284422-111562 + Details
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