Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 7,155	$ 27,970	$ 52,516	$ 82,941
Other comprehensive income (loss), net of tax:
Currency translation adjustments (net of income tax of $0 in 2014 and $1,072 and $533 in 2013)	(16,796)	8,340	(16,899)	2,196
Change in unrecognized net periodic pension costs (net of income tax of $57 and $245 in 2014 and $134 and $400 in 2013)	132	208	351	625
Other (net of income tax of $56 and $72 in 2014 and $8 and $24 in 2013)	(133)	1	(127)	(24)
Total other comprehensive income (loss), net of tax	(16,797)	8,549	(16,675)	2,797
Comprehensive income (loss)	$ (9,642)	$ 36,519	$ 35,841	$ 85,738