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Derivatives - Gain (loss) included in the Statement of Earnings for changes in the fair value of derivatives that do not qualify for hedge accounting (Details) - Not designated as hedging instrument - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | $ 196 | $ 102 | $ 2 | $ (86)
MBS with embedded derivatives | Realized gains (losses) on securities |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | (5) | 3 | 2 | 15
Public company warrants | Realized gains (losses) on securities |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | 0 | (1) | 0 | (1)
Fixed-indexed and variable-indexed annuities (embedded derivative) | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | (5) | 70 | 41 | (643)
Equity index call options | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | 203 | 30 | (42) | 544
Equity index put options | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | 2 | 0 | 1 | 1
Reinsurance contracts (embedded derivative) | Net investment income |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | $ 1 | $ 0 | $ 0 | $ (2)

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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