CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest [Abstract]
Net income (loss)	$ 1,542	$ (1,485)
Unrealized gain (loss) on defined benefit plan, net of tax	856	(74)
Unrealized gain on interest rate swap, net of tax	527
Unrealized foreign currency gain, net of tax	9,442	2,878
Comprehensive income	12,367	1,319
Less: Comprehensive income attributable to noncontrolling interest	(325)	(248)
Total comprehensive income attributable to common stockholders	$ 12,042	$ 1,071