Other Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Component of Other Income (Expense), Nonoperating [Line Items]
Other income (expense)	$ 802	$ 846	$ 787	$ 1,673
Gain (loss) on currency transactions [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other income (expense)	6	347	(724)	1,462
Hedge ineffectiveness
Component of Other Income (Expense), Nonoperating [Line Items]
Other income (expense)	769	566	1,139	167
Other Non-Operating Income (Expense) [Member]
Component of Other Income (Expense), Nonoperating [Line Items]
Other income (expense)	$ 27	$ (67)	$ 372	$ 44