Financial Instruments and Risk Management (Balance Sheet Classification and Fair Value of Derivative Instruments) (Details) - Forward Contracts [Member] - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Not Designated as Hedging Instrument [Member] \| Prepaid Expenses And Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	$ 1,361	$ 1,328
Not Designated as Hedging Instrument [Member] \| Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	180	1,693
Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member] \| Prepaid Expenses And Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	9,805	5,394
Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member] \| Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	1,969	566
Cash Flow Hedging [Member] \| Designated as Hedging Instrument [Member] \| Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative liabilities	$ 106	$ 224

Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

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- Definition

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+ References

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+ References

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