Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 11,130	$ 9,853
Other comprehensive (loss) income:
Foreign currency exchange translation adjustments	104	1,470
Minimum pension liability, net of tax	(649)	(338)
Derivative Instrument	339	0
Other comprehensive (loss) income	(206)	1,132
Comprehensive income	$ 10,924	$ 10,985

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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