Income Taxes - Uncertain Tax Positions (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation of unrecognized tax benefits details [Abstract]
Balance at January 1,	$ 51	$ 52	$ 177
Decrease due to prior year positions	(35)	(5)	(113)
Increase due to current year positions	6	7	7
Reduction in net unrecognized tax benefit resulting from IRS examination	0	0	(17)
Reduction related to lapse of applicable statute of limitations	(5)	(3)	(2)
Balance at December 31,	17	51	52
Unrecognized tax benefits increase (decrease)	(34)
Increase (decrease) in net income resulting from change in gross unrecognized tax benefits	16
Liability for net interest and penalties

The increase (decrease) in net income as a result of increases or decreases to gross unrecognized tax benefits.

No definition available.

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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

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- Definition

This element represents the total of accruals as of the date of the statement of financial position for interest recognized for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity and the amount of statutory penalties for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

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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.

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The net amount of all increases and decreases in unrecognized tax benefits for the period.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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