Derivative Financial Instruments And Hedging Activities (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability, Notional amount	$ 15,998	$ 13,933
Derivative liability, Notional amount	47	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	6,450	0
Derivative asset, Fair value	70	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	500	1,000
Derivative liability, Notional amount	0	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	1,786	0
Derivative liability, Notional amount	6	0
Not Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, Notional amount	14,488	11,909
Derivative asset, Fair value	144	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	5,153	4,122
Derivative asset, Fair value	60	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	8,028	6,327
Derivative asset, Fair value	5	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	1,307	1,460
Derivative asset, Fair value	79	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	7,874	8,041
Derivative liability, Notional amount	42	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	8,124	5,892
Derivative liability, Notional amount	$ 5	$ 19

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ References

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+ References

No definition available.

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