Income Taxes - Income Tax Reconciliation (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Income Tax Disclosure [Abstract]
Income tax expense (benefit) at the U.S. federal tax rate of 35%	$ 245	$ (58)	$ 99
Foreign income tax differential	(36)	(8)	(60)
U.S. permanent book/tax differences	(3)	3	2
Tax audit settlements	(12)	(12)	0
Change in liability for unrecognized tax benefits	12	2	4
Nondeductible transaction costs	1	4	0
U.S. valuation allowance	17	5	0
Japan valuation allowance release	0	0	(40)
Other, net	(1)	(2)	0
Total income tax expense (benefit)	$ 223	$ (66)	$ 5
Federal income tax rate	35.00%	35.00%	35.00%

Income Tax Reconciliation, Change in Liability for Unrecognized Tax Benefits

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- Definition

Income Tax Reconciliation, Federal Capital Loss Valuation Allowance

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Income Tax Reconciliation, Nondeductible Transaction Costs

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Income Tax Reconiliation, Valuation Allowance Release

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

+ References

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to pretax Income or Loss from continuing operations; income tax expense or benefit may include interest and penalties on tax uncertainties based on the entity's accounting policy.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to total foreign income tax expense or benefit. The foreign income tax expense or benefit difference represents the income tax expense or benefit at applicable domestic statutory income tax rates applied to foreign earnings or loss for the period versus the foreign income tax expense or benefit calculated by applying the appropriate foreign tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles and enacted tax laws.

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to all other items not otherwise listed in the existing taxonomy.

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to all income tax settlements for the period.

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