Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 117,992	$ 130,006	$ 108,292
Other comprehensive (loss) income:
Cumulative foreign currency translation adjustments, net of tax of ($2,376), $1,601, and $477	(31,461)	13,874	16,765
Reclassification of cumulative translation adjustment included in net income	2,058	0	0
Defined benefit pension plan net loss:
Net unrecognized losses, net of tax of ($2,447), ($1,016), and ($3,949)	(9,787)	(4,065)	(13,222)
Amortization of previously unrecognized net pension losses included in net income, net of tax of $469, $335, and $0	1,877	1,113	0
Total defined benefit pension plan net loss	(7,910)	(2,952)	(13,222)
Other comprehensive (loss) income	(37,313)	10,922	3,543
Comprehensive income	80,679	140,928	111,835
Less: Comprehensive income attributable to noncontrolling interest	197	0	0
Comprehensive income	$ 80,482	$ 140,928	$ 111,835