v2.4.0.6

Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Income Taxes (Textual) [Abstract]
Effective tax rate	47.00%	49.00%
Domestic federal statutory rate	35.00%
Decrease in unrecognized tax benefits	$ 235
Unrecognized tax benefits	637
Unrecognized tax benefits that if recognized, would affect effective tax rate	$ 411

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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 gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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

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