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

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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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

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

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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.

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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.

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The amount of net gains or losses on foreign currency cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

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Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Hedging (Details) $ in Thousands	3 Months Ended		6 Months Ended
Hedging (Details) $ in Thousands	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($) Derivatives	Jun. 30, 2018 USD ($) Derivatives	Jun. 30, 2017 USD ($) Derivatives	Dec. 31, 2017 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Derivatives, Fair Value [Line Items]
Maximum Length of Time Hedged in Cash Flow Hedge			2 years
Derivative, Number of New Instruments During Period \| Derivatives		6		12
Derivative, New Instruments During Period, Notional Amount		$ 3,300		$ 6,900
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	$ 92	(172)	$ (71)	(143)
Unrealized loss on hedge instruments	(810)	(509)	(810)	(509)	$ (177)	$ (96)	$ (25)	$ (527)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	(393)	101	(562)	574
Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	92
Hedge Loss Recognized in Other Comprehensive Income (Loss)	(301)	(71)	(633)	431
Cost of Sales [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	32	(60)	(25)	(50)
Research and Development Expense [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	45	(84)	(35)	(70)
Selling, General and Administrative Expenses [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	15	$ (28)	(11)	$ (23)
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0		0		508
Other Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Cash Flow Hedge Derivative Instrument Liabilities at Fair Value	(236)		(236)		0
Foreign Exchange Forward [Member]
Derivatives, Fair Value [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months			400
Notional Amount of Foreign Currency Cash Flow Hedge Derivatives	$ 5,548		$ 5,548		$ 13,018
Foreign Exchange Forward [Member] \| Cash Flow Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative, Number of New Instruments During Period \| Derivatives			18
Derivative, New Instruments During Period, Notional Amount			$ 11,600