Derivative Instruments (Maturity Of The Notional Amounts Of Derivative Financial Instruments) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2020 USD ($)
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	$ 49,465
Remaining Life - 1 - 5 Years	76,609
Remaining Life - 6 - 10 Years	34,126
Remaining Life - 11 - 30 Years	38,102
Remaining Life Over - 30 Years	9,444
Remaining Life - Total Years	207,746
Interest Rate Contracts [Member]
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	14,583
Remaining Life - 1 - 5 Years	55,297
Remaining Life - 6 - 10 Years	27,601
Remaining Life - 11 - 30 Years	36,510
Remaining Life Over - 30 Years	1,590
Remaining Life - Total Years	$ 135,581
Derivative maturity date	Apr. 20, 2067
Foreign currency contracts [Member]
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	$ 176
Remaining Life - 1 - 5 Years	387
Remaining Life - 6 - 10 Years	967
Remaining Life - 11 - 30 Years	1,580
Remaining Life - Total Years	$ 3,110
Derivative maturity date	Jun. 17, 2050
Equity market contracts [Member]
Maturity of the notional amounts of derivative financial instruments
Remaining Life Less Than 1 Year	$ 34,706
Remaining Life - 1 - 5 Years	20,925
Remaining Life - 6 - 10 Years	5,504
Remaining Life - 11 - 30 Years	12
Remaining Life Over - 30 Years	7,854
Remaining Life - Total Years	69,001
Credit contracts [Member]
Maturity of the notional amounts of derivative financial instruments
Remaining Life - 6 - 10 Years	54
Remaining Life - Total Years	$ 54