Derivative Instruments and Hedging Activity (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Maximum [Member]
Derivative instruments and hedging activity for the period [Abstract]
Number of months for contracts to mature	18 months
Forward Exchange Contracts [Member] \| Cash Flow Hedges [Member]
Derivative instruments and hedging activity for the period [Abstract]
Derivative, fair value	$ 31,200	$ 44,900
Foreign Currency Denominated Debt, Net Investment Hedging [Member]
Derivative instruments and hedging activity for the period [Abstract]
Carrying value of foreign denominated debt	268,800	$ 261,900
Impact of foreign exchange rates on debt instruments recorded in Other Comprehensive Income	$ 6,900

No definition available.

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- Definition

Refers to number of months for contracts to mature.

+ References

No definition available.

+ Details

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- Definition

Fair value of all asset derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

+ Details

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

+ Details

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- Definition

Amount of increase (decrease) in the cumulative translation adjustment from gain (loss), after tax, on foreign currency derivatives, that are designated as, and are effective as, economic hedges of a net investment in a foreign entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
-Subparagraph (b),(c),(d)
-URI http://asc.fasb.org/extlink&oid=64808268&loc=d3e32211-110900

+ Details

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- Details

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- Details

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