Derivatives Notional Amounts - Not Designated as Hedges (Details) (Not Designated as Hedging Instrument [Member], USD $)	3 Months Ended	12 Months Ended	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Derivative [Line Items]
Notional Amount	$ 79,522,000	$ 79,973,000
Gain (Loss)	(1,535,000)	(1,458,000)
Forward exchange contracts—net
Derivative [Line Items]
Gain (Loss)	(1,535,000)		(345,000)
AUD / USD
Derivative [Line Items]
Notional Amount	6,700,000	7,300,000
Gain (Loss)	259,000	117,000
CAD / USD
Derivative [Line Items]
Notional Amount	7,738,000	6,016,000
Gain (Loss)	(5,000)	(6,000)
CNY / USD
Derivative [Line Items]
Notional Amount	3,205,000	3,200,000
Gain (Loss)	9,000	(14,000)
EUR / USD
Derivative [Line Items]
Notional Amount	52,558,000	53,365,000
Gain (Loss)	(1,851,000)	(1,585,000)
DKK / USD
Derivative [Line Items]
Notional Amount	1,419,000	0
Gain (Loss)	19,000	0
GBP / USD
Derivative [Line Items]
Notional Amount	1,479,000	5,592,000
Gain (Loss)	4,000	18,000
NOK / USD
Derivative [Line Items]
Notional Amount	1,343,000	0
Gain (Loss)	22,000	0
NZD / USD
Derivative [Line Items]
Notional Amount	4,500,000	4,500,000
Gain (Loss)	6,000	12,000
SEK / USD
Derivative [Line Items]
Notional Amount	580,000	0
Gain (Loss)	$ 2,000	$ 0