Income Taxes (Narrative) (Details) $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($)
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits, Increase Resulting from Foreign Currency Translation	$ 7
Income Tax Examination, pre-tax adjustments proposed	192
Income Tax Examination, Estimate of Possible Loss	$ 67

Income Tax Examination, pre-tax adjustments proposed by IRS relating to a current examination

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- References

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- Definition

Estimated amount of loss resulting from an adverse tax position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)(3)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319

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Amount of increase in unrecognized tax benefits resulting from foreign currency translation.

+ 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=65882285&loc=SL6600010-109319

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