Balance Sheet Effect of Derivative Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Notional	$ 104,220	$ 96,452
Fair Value of Derivative Assets	1,610	924
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	(155)	(167)
Derivative Asset	1,455	757
Fair Value of Derivative Liabilities	204	243
Derivative Liability, Fair Value, Amount Not Offset Against Collateral	(155)	(167)
Derivative Liability	49	76
Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Notional	32,843	28,964
Fair Value of Derivative Assets	1,184	670
Fair Value of Derivative Liabilities	0	16
Not Designated as Hedging Instrument [Member] \| Interest Rate Contract [Member]
Derivative [Line Items]
Notional	65,538	62,638
Fair Value of Derivative Assets	182	159
Fair Value of Derivative Liabilities	159	112
Not Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member]
Derivative [Line Items]
Notional	2,138	1,713
Fair Value of Derivative Assets	49	22
Fair Value of Derivative Liabilities	8	4
Not Designated as Hedging Instrument [Member] \| Cross Currency Interest Rate Contract [Member]
Derivative [Line Items]
Notional	3,701	3,137
Fair Value of Derivative Assets	195	73
Fair Value of Derivative Liabilities	$ 37	$ 111

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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-Publisher SEC
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-Section 13
-Sentence Column B

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