Other Income (Expense) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Component of Other Income (Expense), Nonoperating [Line Items]
Other income (expense)	$ 51	$ 427	$ (384)	$ (164)
Gain (loss) on currency translation [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other income (expense)	481	578	198	(391)
Hedge ineffectiveness [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other income (expense)	(623)	(189)	(845)	230
Other non-operating income (expense) [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other income (expense)	$ 193	$ 38	$ 263	$ (3)