Derivative Instruments (Effects Of Qualifying And Non-Qualifying Hedges) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Realized Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total line items in which the effects of fair value or cash flow hedges are recorded	$ (278)	$ (628)
Net Investment Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total line items in which the effects of fair value or cash flow hedges are recorded	1,287	2,478
Interest rate contracts [Member] \| Realized Gain (Loss) [Member] \| Non-Qualifying Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-qualifying hedges gain (loss)	569	926
Equity market contracts [Member] \| Realized Gain (Loss) [Member] \| Non-Qualifying Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-qualifying hedges gain (loss)	45	(413)
GLB Direct And Ceded Embedded Derivative [Member] \| Realized Gain (Loss) [Member] \| Non-Qualifying Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-qualifying hedges gain (loss)	(1)
Embedded derivatives - Reinsurance related [Member] \| Realized Gain (Loss) [Member] \| Non-Qualifying Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-qualifying hedges gain (loss)	(271)	(560)
Indexed Annuity [Member] \| Realized Gain (Loss) [Member] \| Non-Qualifying Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-qualifying hedges gain (loss)	(110)	(349)
Fair Value Hedges [Member] \| Interest rate contracts [Member] \| Net Investment Income [Member] \| Qualifying Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged items	34	58
Derivatives designated as hedging instruments	(34)	(58)
Cash Flow Hedges [Member] \| Interest rate contracts [Member] \| Net Investment Income [Member] \| Qualifying Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	1	2
Cash Flow Hedges [Member] \| Foreign currency contracts [Member] \| Realized Gain (Loss) [Member] \| Qualifying Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	3	4
Cash Flow Hedges [Member] \| Foreign currency contracts [Member] \| Net Investment Income [Member] \| Qualifying Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	$ 8	$ 15

Amount of income (expense) line items in statement of financial position that hedges are recorded

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- Definition

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

+ References

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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