Income Taxes (Details 3) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Unrecognized Tax Benefit Rollforward [Abstract]
Unrecognized Tax Benefits, Beginning Balance	$ 80	$ 146	$ 98
Additions for tax positions related to the current year	0	0	14
Additions for tax positions of prior years	1	11	66
Reductions for tax positions of prior years	0	(68)	(25)
Settlements	(7)	(9)	(5)
Statute of limitations	(9)	0	(2)
Unrecognized Tax Benefits, Ending Balance	65	80	146
Unrecognized Tax Benefits That Would Impact Effective Tax Rate	25
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense [Abstract]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	1	6	13
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued [Abstract]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	14	16
Foreign Source Income [Abstract]
Foreign Earnings Repatriated	$ (654)	$ 1,180	$ 2,336

-- None. No documentation exists for this element. --

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Amount of foreign earnings repatriated from subsidiaries outside the country of domicile.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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- Definition

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

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