Derivatives and Hedging Activities (Details 1) - Fair Value Hedging [Member] - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Expense [Member] \| Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative contract	$ (184)	$ (83)	$ (143)
Hedged item	163	93	148
Net hedge ineffectiveness	(21)	10	5
Other Revenues [Member] \| Total Return Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative contract	0	0
Hedged item	0	0
Net hedge ineffectiveness	$ 0	$ 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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