Income Taxes (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Unrecognized Tax Benefit Rollforward [Abstract]
Unrecognized Tax Benefits, Beginning Balance	$ 146us-gaap_UnrecognizedTaxBenefits	$ 98us-gaap_UnrecognizedTaxBenefits	$ 157us-gaap_UnrecognizedTaxBenefits
Additions for tax positions related to the current year	0	14	0
Additions for tax positions of prior years	11	66	81
Reductions for tax positions of prior years	(68)	(25)	(67)
Settlements	(9)	(5)	(72)
Statute of limitations	0	(2)	(1)
Unrecognized Tax Benefits, Ending Balance	80us-gaap_UnrecognizedTaxBenefits	146us-gaap_UnrecognizedTaxBenefits	98us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits That Would Impact Effective Tax Rate	37
Significant Change In Unrecognized Tax Benefits Is Reasonably Possible Amount Of Unrecorded Benefit	5
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense [Abstract]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	6	13	4
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued [Abstract]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	16	15
Foreign Source Income [Abstract]
Foreign Earnings Repatriated	1,180us-gaap_ForeignEarningsRepatriated	2,336us-gaap_ForeignEarningsRepatriated	3,356us-gaap_ForeignEarningsRepatriated
Undistributed Income Of Certain Consolidated Foreign Subsidiaries	1,019
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries	$ 357

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Amount of deferred tax liability not recognized because of the exceptions to comprehensive recognition of deferred taxes related to undistributed earnings of foreign subsidiaries.

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Amount of foreign earnings repatriated from subsidiaries outside the country of domicile.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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