Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 28,176	$ 7,155	$ 71,342	$ 52,516
Other comprehensive income (loss), net of tax:
Currency translation adjustments (net of income tax of $0 in 2015 and 2014)	2,054	(16,796)	(19,281)	(16,899)
Change in unrecognized net periodic pension costs (net of income tax of $117 and $402 in 2015 and $57 and $245 in 2014)	284	132	802	351
Other (net of income tax of $0 in 2015 and $56 and $72 in 2014)	(105)	(133)	(75)	(127)
Total other comprehensive income (loss), net of tax	2,233	(16,797)	(18,554)	(16,675)
Comprehensive income (loss)	$ 30,409	$ (9,642)	$ 52,788	$ 35,841