Fair Value Measurements Table - Reconciliation of Level 3 Derivatives (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2014 Level 3 [Member] Fair Value, Measurements, Recurring [Member]	Dec. 31, 2013 Level 3 [Member] Fair Value, Measurements, Recurring [Member]
Balance, December 31, 2013		$ (20)	$ (19)
Net unrealized loss included in other income (expense)	1
Balance, March 31, 2014		$ (20)	$ (19)

Amount of realized and unrealized gain (loss) included in earnings, which have arisen from the use of significant unobservable inputs (level 3) to measure fair value of assets, liabilities, and financial instruments classified in shareholders' equity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration