Derivatives - Designated Hedge Gain (Loss) (Details) (Foreign currency exchange contracts, USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Foreign currency exchange contracts
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Instruments, Effective Portion Reclassified from AOCI to Earnings	$ 51	$ 43
Derivative Instruments, Effective Portion Recognized in Other Comprehensive Income	$ (16)	$ (51)

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624177-113959

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Period Type:	duration