Derivative Financial Instruments And Hedging Activities (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, Notional amount	$ 5,041	$ 0
Derivative asset, Fair value	60	0
Designated as Hedging Instrument [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability, Notional amount	5,510	1,000
Derivative liability, Fair value	24	6
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	3,450	0
Derivative asset, Fair value	58	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	3,500	1,000
Derivative liability, Fair value	20	6
Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Other Assets [Member] \| Interest Rate Swaps [Member] \| Level 3 [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, Notional amount	889	0
Derivative asset, Fair value	1	0
Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Other Assets [Member] \| Foreign Currency Swaps [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, Notional amount	702	0
Derivative asset, Fair value	1	0
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	1,870	0
Derivative liability, Fair value	3	0
Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member] \| Other Liabilities [Member] \| Foreign Currency Swaps [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative liability, Notional amount	140	0
Derivative liability, Fair value		0
Not Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, Notional amount	15,588	11,909
Derivative asset, Fair value	101	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	5,483	4,122
Derivative asset, Fair value	22	8
Not Designated as Hedging Instrument [Member] \| Other Assets [Member] \| Interest Rate Options [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, Notional amount	8,734	6,327
Derivative asset, Fair value	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	1,371	1,460
Derivative asset, Fair value	71	48
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative liability, Notional amount	17,717	13,933
Derivative liability, Fair value	36	43
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	7,670	8,041
Derivative liability, Fair value	29	24
Not Designated as Hedging Instrument [Member] \| Other Liabilities [Member] \| Interest Rate Options [Member] \| Level 2 [Member]
Derivatives, Fair Value [Line Items]
Derivative liability, Notional amount	10,047	5,892
Derivative liability, Fair value	$ 7	$ 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=64837297&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6519104

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+ References

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+ References

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- Definition

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+ References

No definition available.

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