Income Taxes Income Taxes (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Income Tax Uncertainties [Abstract]
Unrecognized tax benefits that would impact our effective tax rate if recognized	$ 23
Unrecognized Tax Benefits [Abstract]
Unrecognized Tax Benefits, Beginning Balance	0
Additions for tax positions related to current year	(1)
Additions for tax positions of prior years	24
Reductions for tax positions of prior years	0
Settlements	0
Unrecognized Tax Benefits, Ending Balance	$ 23

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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-Name Accounting Standards Codification

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

+ References

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The gross amount of increases 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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