Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 12,583	$ 4,763	$ 35,631	$ 5,523
Other comprehensive (loss) income:
Foreign currency exchange translation adjustments	(1,529)	1,130	(5,363)	5,209
Minimum pension liability, net of tax	(1,060)	(546)	(1,992)	(1,830)
Other comprehensive (loss) income	(2,589)	584	(7,355)	3,379
Comprehensive income	$ 9,994	$ 5,347	$ 28,276	$ 8,902

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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