Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - 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 (loss)	$ 13,628	$ 7,748	$ 22,936	$ (707)
Other comprehensive income (loss), net of reclassification adjustments:
Unrealized losses on interest rate swap contracts	(234)	(74)	(122)	(45)
Foreign currency translation adjustments	(907)	1,389	(2,849)	3,388
Other comprehensive income (loss)	(1,141)	1,315	(2,971)	3,343
Comprehensive income	$ 12,487	$ 9,063	$ 19,965	$ 2,636

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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