Derivative and Financial Instruments - FX Notional (Details 5) In Millions, unless otherwise specified	Sep. 30, 2012 Sell U.S. dollar, buy other currencies [Member] USD ($)	Dec. 31, 2011 Sell U.S. dollar, buy other currencies [Member] USD ($)	Sep. 30, 2012 Sell euro, buy other currencies [Member] EUR (€)	Dec. 31, 2011 Sell euro, buy other currencies [Member] EUR (€)	Sep. 30, 2012 Buy U.S. dollar, sell other currencies [Member] USD ($)	Dec. 31, 2011 Buy U.S. dollar, sell other currencies [Member] USD ($)	Sep. 30, 2012 Buy British pound, sell other currencies [Member] GBP (£)	Dec. 31, 2011 Buy British pound, sell other currencies [Member] GBP (£)	Sep. 30, 2012 Buy Euro Sell British Pound [Member] EUR (€)	Dec. 31, 2011 Buy Euro Sell British Pound [Member] EUR (€)
Trading Activity, Gains and Losses, Net [Line Items]
Net notional position of foreign currency exchange derivatives	$ 285	$ 1,949	€ 0	€ 61	$ 477	$ 0	£ 3,709	£ 0	€ 176	€ 0

Aggregate notional amount of all foreign currency derivatives not designated as hedging instruments. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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