Derivative Financial Instruments And Hedging Activities (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Notional Amount	$ 17,230	$ 13,933
Derivative Liability	55	43
Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member] \| Other Assets [Member] \| Interest Rate Swaps [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	1,000	0
Derivative Asset	19	0
Designated as Hedging Instrument [Member] \| Fair Value Hedging [Member] \| Other Liabilities [Member] \| Interest Rate Swaps [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Notional Amount	2,750	1,000
Derivative Liability	24	6
Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Other Liabilities [Member] \| Interest Rate Swaps [Member] \| Level 3 [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Notional Amount	431	0
Derivative Liability	0	0
Not Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	15,033	11,909
Derivative Asset	54	75
Not Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest Rate Swaps [Member] \| Level 3 [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	5,716	4,122
Derivative Asset	25	8
Not Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest Rate Caps [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	8,410	6,327
Derivative Asset	8	19
Not Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Foreign Currency Swaps [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Notional Amount	907	1,460
Derivative Asset	21	48
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest Rate Swaps [Member] \| Level 3 [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Notional Amount	8,445	8,041
Derivative Liability	32	24
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest Rate Caps [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Notional Amount	7,956	5,892
Derivative Liability	8	19
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Foreign Currency Swaps [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Notional Amount	829	0
Derivative Liability	$ 15	$ 0

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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+ References

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+ References

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+ References

No definition available.

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