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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
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | $ (12) | $ (7) | $ (54) | $ (113)
MBS with embedded derivatives | Realized gains on securities |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | 0 | (4) | (3) | 0
Public company warrants | Realized gains on securities |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | (1) | 1 | (1) | 0
Fixed-indexed annuities (embedded derivative) | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | (127) | (109) | (386) | (188)
Equity index call options | Annuity benefits |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | 116 | 105 | 338 | 81
Reinsurance contracts (embedded derivative) | Net investment income |  |  |  |
Derivative, Gain (Loss) on Derivative, Net [Abstract] |  |  |  |
Derivative | $ 0 | $ 0 | $ (2) | $ (6)

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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/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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- References No definition available. + Details
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