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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 | 6 Months Ended
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Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | $ (213) | $ (98) | $ (194) | $ (188)
MBS with embedded derivatives | Realized gains (losses) on securities |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | 3 | 6 | 7 | 12
Fixed-indexed and variable-indexed annuities (embedded derivative) | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | (601) | (251) | 46 | (713)
Equity index call options | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | 383 | 148 | (245) | 514
Equity index put options | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | 5 | 0 | (1) | 1
Reinsurance contracts (embedded derivative) | Net investment income |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | $ (3) | $ (1) | $ (1) | $ (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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- References No definition available. + Details
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