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Investments - Holding gains (losses) on equity securities still held (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Holding Gains (Losses) on Equity Securities Still Held [Line Items] |  |  |
Realized gains (losses) on securities | $ 110 | $ (75) | $ 155
Investment income | 742 | 467 | 538
Equity securities |  |  |
Holding Gains (Losses) on Equity Securities Still Held [Line Items] |  |  |
Realized gains (losses) on securities | 110 | (70) | 155
Equity securities still owned | Equity securities |  |  |
Holding Gains (Losses) on Equity Securities Still Held [Line Items] |  |  |
Net holding gains (losses) on equity securities | 119 | (32) | 126
Realized gains (losses) on securities | Equity securities still owned | Equity securities |  |  |
Holding Gains (Losses) on Equity Securities Still Held [Line Items] |  |  |
Realized gains (losses) on securities | 65 | (44) | 105
Investment income | Equity securities still owned | Equity securities |  |  |
Holding Gains (Losses) on Equity Securities Still Held [Line Items] |  |  |
Investment income | $ 54 | $ 12 | $ 21

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- Definition holding gains (losses) on equity securities still held + References No definition available. + Details
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- Definition Net holding gains (losses) on equity securities in net earnings on securities that were still owned. All equity securities other than those accounted for under the equity method are carried at fair value through net earnings. + References No definition available. + Details
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- Definition Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.2) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 + 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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