Derivative Instruments (Effects Of Qualifying And Non-Qualifying Hedges) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 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	$ (11)	$ (491)
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	1,235	3,842
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	113	254
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)	699	1,625
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		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)	(2)
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	44	101
Derivatives designated as hedging instruments	(44)	(101)
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	(62)	(145)
Derivatives designated as hedging instruments	62	145
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	5	9
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	10	25
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)	173	(241)
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)	(23)	(372)
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)	(715)	(800)
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)	$ (30)	$ (336)

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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