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Tax (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Tax (Textual) [Abstract]
Effective tax rate	32.10%	32.00%	31.50%	31.90%
U.S. federal statutory rate			35.00%
Unrecognized tax benefit	$ 131		$ 131
Unrecognized tax benefits that would reduce income tax	58		58
Material changes in unrecognized tax benefits	$ 0		$ 0

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A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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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 gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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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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