Derivative Instruments (Effects Of Qualifying And Non-Qualifying Hedges) (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
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	$ (610)
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	5,223
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	326
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)	984
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	3
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	(5)
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	63
Derivatives designated as hedging instruments	(63)
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	(93)
Derivatives designated as hedging instruments	93
Foreign currency 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)	(1)
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	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	35
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)	(137)
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)	306
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)	(324)
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)	$ (742)

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.

+ References

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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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