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Derivatives - Narrative (Details) € in Thousands, ₩ in Thousands, ¥ in Thousands, ¥ in Thousands, £ in Thousands, kr in Thousands, kr in Thousands, SFr in Thousands, R$ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($)	Mar. 31, 2018 HKD ($) derivative_instrument	Mar. 31, 2018 DKK (kr) derivative_instrument	Mar. 31, 2018 MXN ($) derivative_instrument	Mar. 31, 2018 CNY (¥) derivative_instrument	Mar. 31, 2018 KRW (₩) derivative_instrument	Mar. 31, 2018 GBP (£) derivative_instrument	Mar. 31, 2018 CAD ($) derivative_instrument	Mar. 31, 2018 JPY (¥) derivative_instrument	Mar. 31, 2018 SGD ($) derivative_instrument	Mar. 31, 2018 SEK (kr) derivative_instrument	Mar. 31, 2018 CHF (SFr) derivative_instrument	Mar. 31, 2018 BRL (R$) derivative_instrument	Mar. 31, 2018 USD ($) derivative_instrument	Mar. 31, 2018 EUR (€) derivative_instrument	Mar. 31, 2018 AUD ($) derivative_instrument	Dec. 31, 2017 USD ($)	Aug. 05, 2016 USD ($)
Derivative [Line Items]
Deferred taxes used to offset fair value of interest rate swap																	$ (1,500)
Maturity of derivative contract (up to)	2 years
Revenue and cost of sales
Derivative [Line Items]
Amount expected to be reclassified from accumulated other comprehensive income to earnings in next twelve months, gross	$ 23
Amount expected to be reclassified from accumulated other comprehensive income to earnings in next twelve months, net of tax	17
Interest expense
Derivative [Line Items]
Amount expected to be reclassified from accumulated other comprehensive income to earnings in next twelve months, gross	1,700
Amount expected to be reclassified from accumulated other comprehensive income to earnings in next twelve months, net of tax	$ 1,300
Interest rate swap
Derivative [Line Items]
Notional amount of derivative																		$ 42,500
Fixed rate																		1.12%
Deferred taxes used to offset fair value of interest rate swap														$ (2,000)
Interest rate swap | Maximum
Derivative [Line Items]
Notional amount of derivative																		$ 175,000
Foreign currency forward contracts | Designated as hedging instrument
Derivative [Line Items]
Average number of contracts entered into per month | derivative_instrument		100	100	100	100	100	100	100	100	100	100	100	100	100	100	100
Foreign currency forward contracts | Not designated as hedging instrument
Derivative [Line Items]
Notional amount of derivative		$ 11,000	kr 2,230	$ 17,860	¥ 24,500	₩ 1,800,000	£ 1,497	$ 2,738	¥ 255,000	$ 6,200	kr 7,987	SFr 255	R$ 8,500		€ 23,966	$ 6,993
Average number of contracts entered into per month | derivative_instrument		20	20	20	20	20	20	20	20	20	20	20	20	20	20	20

X

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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X

- Definition

Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Tax

+ References

No definition available.

+ Details

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- Definition

Cash Flow Hedge Gain (Loss) To Be Reclassified Within Twelve Months, Gross

+ References

No definition available.

+ Details

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X

- Definition

Derivative, Average Number of Contracts Entered Into Per Month

+ References

No definition available.

+ Details

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X

- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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X

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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X

- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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