SCHEDULE I - Parent Company Information - Condensed Statements of Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Net income	$ 43,231	$ 62,158	$ 14,069
Other comprehensive (loss) income:
Currency translation adjustment	(770)	896	(868)
Derivative instruments
Unrealized gain on derivative instruments	533	1,061	69
Net (loss) gain recognized in other comprehensive income	(237)	1,957	(799)
Tax benefit (expense) related to items of other comprehensive income	54	(686)	275
Total comprehensive income	43,048	63,429	13,545
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Net income	43,231	62,158	14,069
Other comprehensive (loss) income:
Currency translation adjustment	(770)	896	(868)
Derivative instruments
Unrealized gain on derivative instruments	533	1,061	69
Net (loss) gain recognized in other comprehensive income	(237)	1,957	(799)
Tax benefit (expense) related to items of other comprehensive income	54	(686)	275
Other comprehensive (loss) income	(183)	1,271	(524)
Total comprehensive income	$ 43,048	$ 63,429	$ 13,545