Derivatives and Hedging Activities (Details 1) (Fair Value Hedging [Member], USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Other Expense [Member] \| Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative contract	$ 63	$ (51)
Hedged item	(57)	51
Net hedge ineffectiveness	6	0
Other Income [Member] \| Total Return Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative contract	0	13
Hedged item	0	(13)
Net hedge ineffectiveness	$ 0	$ 0

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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