Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Total provision (benefit) for income taxes
Total income tax provision (benefit)	$ (11)	$ 155	$ 139	$ 273
Income tax reconciliation to US federal statutory rate
Amount computed using the statutory rate	(15)	148	125	260
Increase (decrease) in taxes resulting from:
State and local income taxes, net of federal effect	(1)	4	3	9
Net effect of different tax rates in non-U.S. jurisdictions	5	0	11	1
Other	0	3	0	3
Total income tax provision (benefit)	$ (11)	$ 155	$ 139	$ 273
Income Taxes (Textuals) [Abstract]
Federal statutory tax rate			35.00%

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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.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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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 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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