Income Taxes Level 4 (Details) - Unrecognized Tax Benefits (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of year	$ 70us-gaap_UnrecognizedTaxBenefits	$ 92us-gaap_UnrecognizedTaxBenefits
Additions based on tax positions related to the current year	7	6
Additions for tax positions of prior years	2	8
Reductions for tax positions of prior years	(7)	(38)
Settlements	(1)	0
Foreign currency translation	(5)	2
Balance at end of year	66us-gaap_UnrecognizedTaxBenefits	70us-gaap_UnrecognizedTaxBenefits	92us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits, Period Increase (Decrease)	1
Income Tax Examination, Penalties Expense	3	6	(2)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	34	31
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	66
Maximum [Member]
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Amount of Unrecognized Tax Benefits Expected to Be Recognized within the Next 12 Months	$ 1

Amount of Unrecognized Tax Benefits Expected to Be Recognized within the Next 12 Months

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The amount of estimated penalties recognized in the period arising from income tax examinations.

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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 foreign currency translation.

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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 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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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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

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