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	$ (117)	$ (480)
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	1,355	2,606
Interest and Debt Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Line Items in which the Effects of Fair Value or Cash Flow Hedges are Recorded	70	141
Interest Rate Contracts [Member] \| Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] \| Realized Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-Qualifying Hedges Gain (Loss)	569	926
Interest Rate Contracts [Member] \| Cash Flow Hedges [Member] \| Designated as Hedging Instrument [Member] \| Net Investment Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	1	2
Interest Rate Contracts [Member] \| Cash Flow Hedges [Member] \| Designated as Hedging Instrument [Member] \| Interest and Debt Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income		(1)
Interest Rate Contracts [Member] \| Fair Value Hedges [Member] \| Designated as Hedging Instrument [Member] \| Net Investment Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged items	34	58
Derivatives designated as hedging instruments	(34)	(58)
Interest Rate Contracts [Member] \| Fair Value Hedges [Member] \| Designated as Hedging Instrument [Member] \| Interest and Debt Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged items	(49)	(83)
Derivatives designated as hedging instruments	49	83
Foreign currency contracts [Member] \| Cash Flow Hedges [Member] \| Designated as Hedging Instrument [Member] \| Realized Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	3	4
Foreign currency contracts [Member] \| Cash Flow Hedges [Member] \| Designated as Hedging Instrument [Member] \| Net Investment Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	8	15
Equity market contracts [Member] \| Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] \| Realized Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-Qualifying Hedges Gain (Loss)	45	(413)
Indexed Annuity And IUL Contracts [Member] \| Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] \| Realized Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-Qualifying Hedges Gain (Loss)	(110)	(349)
Embedded derivatives - GLB [Member] \| Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] \| Realized Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-Qualifying Hedges Gain (Loss)	(371)	(85)
Embedded derivatives - Reinsurance related [Member] \| Derivative Instruments Not Designated and Not Qualifying as Hedging Instruments [Member] \| Realized Gain (Loss) [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Non-Qualifying Hedges Gain (Loss)	$ (133)	$ (307)

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

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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.

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

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