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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 | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | $ (106) | $ (103) | $ (103)
MBS with embedded derivatives | Realized gains (losses) on securities |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | 10 | (7) | (6)
Public company warrants | Realized gains (losses) on securities |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | (1) | (3) | 0
Fixed-indexed and variable-indexed annuities (embedded derivative) | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net | [1] | (919) | 204 | (589)
Equity index call options | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | 804 | (298) | 494
Equity index put options | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | 2 | (1) | 0
Reinsurance contract (embedded derivative) | Net investment income |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net |  | $ (2) | $ 2 | $ (2)
[1] | The change in fair value of the embedded derivative includes a favorable adjustment related to unlocking of actuarial assumptions of $181 million in 2019 and losses of $44 million in 2018 and $25 million in 2017.

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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=109980867&loc=SL5618551-113959 + Details
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