CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest [Abstract]
Net (loss) income	$ (1,485)	$ 11,777
Foreign currency translation adjustment	2,881	(6,160)
Unrealized loss on defined benefit plan, net of tax	(74)	(1,813)
Unrealized foreign currency loss, net of tax	(3)	(498)
Comprehensive income	1,319	3,306
Less: Comprehensive income attributable to noncontrolling interest	(248)	(645)
Total comprehensive income attributable to common stockholders	$ 1,071	$ 2,661