Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Consolidated net income	$ 60,762	$ 25,598	$ 43,388
Currency translation adjustment, net of tax	(3,993)	(10,436)	(8,608)
Comprehensive income allocated to common stockholders	$ 56,769	$ 15,162	$ 34,780