Financial Derivatives (Derivatives Designated As Hedging Instruments Under GAAP) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Derivative [Line Items]
Derivative Asset, Fair Value	$ 4,804	$ 4,793
Derivative Liability, Fair Value	3,834	3,934
Derivative Notional Amount	436,413	381,256
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Asset, Fair Value	1,228	1,189
Derivative Liability, Fair Value	264	364
Derivative Notional Amount	39,529	36,197
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Asset, Fair Value	3,576	3,604
Derivative Liability, Fair Value	3,570	3,570
Derivative Notional Amount	396,884	345,059
Fair Value Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Asset, Fair Value	887	925
Derivative Liability, Fair Value	209	296
Derivative Notional Amount	23,317	20,522
Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Receive Fixed Swaps [Member]
Derivative [Line Items]
Derivative Asset, Fair Value	876	871
Derivative Liability, Fair Value	93	230
Derivative Notional Amount	18,860	16,446
Fair Value Hedging [Member] | Designated as Hedging Instrument [Member] | Pay Fixed Swaps [Member]
Derivative [Line Items]
Derivative Asset, Fair Value	11	54
Derivative Liability, Fair Value	116	66
Derivative Notional Amount	4,457	4,076
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative Asset, Fair Value	341	264
Derivative Liability, Fair Value	12	58
Derivative Notional Amount	15,223	14,737
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | One Month Libor [Member]
Derivative [Line Items]
Derivative Variable Interest Rate	41.00%	43.00%
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Three Month Libor [Member]
Derivative [Line Items]
Derivative Variable Interest Rate	59.00%	57.00%
Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] | Receive Fixed Swaps [Member]
Derivative [Line Items]
Derivative Asset, Fair Value	341	264
Derivative Liability, Fair Value	12	58
Derivative Notional Amount	15,223	14,737
Net Investment Hedging [Member] | Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative Liability, Fair Value	43	10
Derivative Notional Amount	$ 989	$ 938