Reclassifications from Accumulated Other Comprehensive Income - AOCI Roll Forward (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014 Net cumulative currency translation gains (losses)	Mar. 31, 2014 Net unrealized losses on qualifying cash flow hedges	Mar. 31, 2014 Net unrecognized losses related to pension and severance plans		Dec. 31, 2013 Net unrecognized losses related to pension and severance plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	$ (25,783)	$ (26,768)	$ (469)	$ (5,654)	$ (19,660)	[1]
Other comprehensive income (loss) before reclassifications	(1,372)		16	(1,046)	(342)
Amounts reclassified from accumulated other comprehensive income	1,404		252	852	300
Net current-period other comprehensive income	32		268	(194)	(42)
Balance at end of period	(25,751)	(26,768)	(201)	(5,848)	(19,702)	[1]
Deferred tax liability					$ 271		$ 530

[1] Net of deferred tax liability of $271, and $530 as of March 31, 2014 and December 31, 2013, respectively.