Income Taxes (Details 2) (USD $) In Millions	12 Months Ended
Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Income (Loss) before Taxes by Domestic and Foreign Sources (Table Amounts) [Abstract]
Domestic income	$ 2,319	$ 1,944	$ 1,739
Foreign income	47	126	102
Earnings from continuing operations before income taxes	$ 2,366	$ 2,070	$ 1,841

The portion of earnings (loss) from continuing operations before income taxes that is attributable to domestic operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
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The portion of earnings (loss) from continuing operations before income taxes that is attributable to foreign operations, which is defined as income (loss) generated from operations located outside the entity's country of domicile.

+ References

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- Definition

Sum of operating profit and nonoperating income (expense) before income (loss) from equity method investments, income taxes, extraordinary items, cumulative effects of changes in accounting principles, and noncontrolling interest.

+ References

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-Number 210
-Section 08
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