Derivative Financial Instruments and Risk Management (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Maximum Length of Time Hedged in Foreign Currency Cash Flow Hedge	P5Y
Deferred net losses, foreign currency exchange rate risk, to be reclassified from equity to current earnings over the next twelve months	$ 44
Deferred net losses, interest rate risk, to be reclassified from equity to current earnings over the next twelve months	$ 4
Commodity forward and option contracts, maximum period (in years)	5 years

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80748-113994

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Data Type:	xbrli:stringItemType
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Period Type:	duration