Derivative Instruments (Maturity Of The Notional Amounts Of Derivative Financial Instruments) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2016 USD ($)
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	$ 29,499
Remaining Life - 1 - 5 Years	34,617
Remaining Life - 6 - 10 Years	23,661
Remaining Life - 11 - 30 Years	13,476
Remaining Life Over - 30 Years	1,663
Remaining Life - Total Years	102,916
Interest rate contracts [Member]
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	10,629	[1]
Remaining Life - 1 - 5 Years	25,755	[1]
Remaining Life - 6 - 10 Years	21,506	[1]
Remaining Life - 11 - 30 Years	12,843	[1]
Remaining Life Over - 30 Years	1,213	[1]
Remaining Life - Total Years	$ 71,946	[1]
Derivative maturity date	Apr. 01, 2067
Foreign currency contracts [Member]
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	$ 229	[2]
Remaining Life - 1 - 5 Years	120	[2]
Remaining Life - 6 - 10 Years	277	[2]
Remaining Life - 11 - 30 Years	616	[2]
Remaining Life Over - 30 Years		[2]
Remaining Life - Total Years	$ 1,242	[2]
Derivative maturity date	Dec. 01, 2045
Equity market contracts [Member]
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	$ 18,556
Remaining Life - 1 - 5 Years	8,742
Remaining Life - 6 - 10 Years	1,872
Remaining Life - 11 - 30 Years	17
Remaining Life Over - 30 Years	450
Remaining Life - Total Years	29,637
Credit contracts [Member]
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	85
Remaining Life - 1 - 5 Years
Remaining Life - 6 - 10 Years	6
Remaining Life - 11 - 30 Years
Remaining Life Over - 30 Years
Remaining Life - Total Years	$ 91

[1] As of September 30, 2016, the latest maturity date for which we were hedging our exposure to the variability in future cash flows for these instruments was April 2067.

[2] As of September 30, 2016, the latest maturity date for which we were hedging our exposure to the variability in future cash flows for these instruments was December 2045.