Derivatives and Hedging Activities (Details 1) (Fair Value Hedging [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Expense [Member] \| Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative contract	$ (143)	$ (370)	$ (178)
Hedged item	148	351	132
Net hedge ineffectiveness	5	(19)	(46)
Other Revenues [Member] \| Total Return Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative contract	11	15	(53)
Hedged item	(11)	(15)	54
Net hedge ineffectiveness	$ 0	$ 0	$ 1

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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Amount of gain (loss)recognized in the income statement from the hedging ineffectiveness of a fair value hedge.

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