CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 10,450	$ 13,125	$ 21,504	$ 24,794
Other comprehensive (loss) income:
Foreign currency translation adjustments	(11,149)	11,784	(8,604)	14,513
Pension liability adjustment, net of tax	199	172	397	344
Unrealized (loss) gain on hedging activities, net of tax	(27)	(44)	75	(44)
Comprehensive (loss) income	$ (527)	$ 25,037	$ 13,372	$ 39,607

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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