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Investments - Realized capital gains and losses by transaction type (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Investments [Abstract] |  |  |  |
Sales | $ 80 | $ 214 | $ 441 | $ 762
Credit Losses | (12) | 7 | 2 | (29)
Valuation of equity investments | (9) | 128 | 321 | (198)
Valuation and settlements of derivative instruments | 46 | (30) | 54 | 62
Realized capital gains (losses) | $ 105 | $ 319 | $ 818 | $ 597

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- Definition Amount of unrealized and realized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity), investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and investment in debt security measured at fair value with change in fair value recognized in net income (trading). + References No definition available. + Details
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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959 + Details
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