Derivative Financial Instruments and Risk Management (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate contracts, Amount of Gains (Losses) Reclassified from AOCI to Earnings (Effective Portion)	$ (1)	$ (6)	$ (2)	$ (12)
Interest rate contracts, Recognized in Earnings (Ineffective Portion)	(1)	0	(1)	1
Gain (Losses) on derivatives not designated as hedging instruments	(5)	(2)	2	(2)
Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Interest rate contracts, Amount of Gains (Losses) Reclassified from AOCI to Earnings (Effective Portion)	(1)	(6)	(2)	(12)
Interest rate contracts, Recognized in Earnings (Ineffective Portion)	0	0	0	0
Other Income (Expense)
Derivative Instruments, Gain (Loss) [Line Items]
Gains (Losses) on Derivatives	6	42	(3)	(11)
Gains (Losses) on Borrowings	(5)	(40)	10	12
Interest rate contracts, Amount of Gains (Losses) Reclassified from AOCI to Earnings (Effective Portion)	0	0	0	0
Interest rate contracts, Recognized in Earnings (Ineffective Portion)	(1)	0	(1)	1
Foreign exchange contracts, Gains (Losses) on derivatives not designated as hedging instruments	(5)	(2)	2	(2)
Interest rate contracts, Gains (Losses) on derivatives not designated as hedging instruments	$ 0	$ 0	$ 0	$ 0

The amount of net gains or losses on a cash flow hedge reclassified in the period to earnings from accumulated other comprehensive income.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Net gain (loss) from the increase (decrease) in fair value of derivative instrument not designated as hedging instrument.

+ References

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

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44

-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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Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments.

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Amount of unrealized gain (loss) included in earnings for the period related to the fair value of the hedged item in an interest rate fair value hedge, which was offset by the gain (loss) on the hedging instrument to the extent that the fair value hedge is determined to be effective.

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-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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Amount of unrealized gain (loss) related to the fair value of interest rate derivatives designated as fair value hedging instruments. Recognized in earnings and offsets the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

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

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Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 45

-Subparagraph b(1)

-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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