Derivatives Notional Amounts - Designated as Hedges (Details) (Designated as Hedging Instrument [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Notional Amount	$ 88,293	$ 83,942
Unrealized Gain (Loss)	1,471	(548)
USD / AUD
Derivative [Line Items]
Notional Amount	925	1,250
Unrealized Gain (Loss)	92	65
USD / CAD
Derivative [Line Items]
Notional Amount	2,968	3,570
Unrealized Gain (Loss)	(282)	(63)
USD / CHF
Derivative [Line Items]
Notional Amount	72	111
Unrealized Gain (Loss)	0	0
USD / EUR
Derivative [Line Items]
Notional Amount	33,883	25,524
Unrealized Gain (Loss)	3,501	0
USD / GBP
Derivative [Line Items]
Notional Amount	929	1,199
Unrealized Gain (Loss)	23	3
USD / NZD
Derivative [Line Items]
Notional Amount	5,861	7,018
Unrealized Gain (Loss)	(58)	(55)
USD / SEK
Derivative [Line Items]
Notional Amount	359	594
Unrealized Gain (Loss)	38	1
USD / MXP
Derivative [Line Items]
Notional Amount	7,650	10,297
Unrealized Gain (Loss)	(696)	(657)
EUR / AUD
Derivative [Line Items]
Notional Amount	324	452
Unrealized Gain (Loss)	(15)	5
EUR / CAD
Derivative [Line Items]
Notional Amount	410	580
Unrealized Gain (Loss)	(16)	(1)
EUR / CHF
Derivative [Line Items]
Notional Amount	377	505
Unrealized Gain (Loss)	41	(2)
EUR / DKK
Derivative [Line Items]
Notional Amount	445	643
Unrealized Gain (Loss)	(3)	(3)
EUR / GBP
Derivative [Line Items]
Notional Amount	18,687	11,906
Unrealized Gain (Loss)	(1,466)	23
EUR / SEK
Derivative [Line Items]
Notional Amount	1,987	2,917
Unrealized Gain (Loss)	(21)	(9)
EUR / NOK
Derivative [Line Items]
Notional Amount	1,053	1,490
Unrealized Gain (Loss)	9	43
EUR / NZD
Derivative [Line Items]
Notional Amount	4,785	7,074
Unrealized Gain (Loss)	477	60
AUD / CAD
Derivative [Line Items]
Notional Amount	1,199	1,538
Unrealized Gain (Loss)	0	30
AUD / CHF
Derivative [Line Items]
Notional Amount	67	93
Unrealized Gain (Loss)	6	1
AUD / NZD
Derivative [Line Items]
Notional Amount	375	537
Unrealized Gain (Loss)	26	19
AUD / SEK
Derivative [Line Items]
Notional Amount	43	61
Unrealized Gain (Loss)	(2)	(1)
CAD / SEK
Derivative [Line Items]
Notional Amount	137	182
Unrealized Gain (Loss)	(5)	(1)
GBP / AUD
Derivative [Line Items]
Notional Amount	468	656
Unrealized Gain (Loss)	25	22
GBP / CHF
Derivative [Line Items]
Notional Amount	283	331
Unrealized Gain (Loss)	7	(1)
GBP / SEK
Derivative [Line Items]
Notional Amount	2,149	1,035
Unrealized Gain (Loss)	(164)	(2)
DKK / CHF
Derivative [Line Items]
Notional Amount	210	269
Unrealized Gain (Loss)	(25)	(2)
DKK / SEK
Derivative [Line Items]
Notional Amount	1,542	2,497
Unrealized Gain (Loss)	(24)	(44)
NOK / CHF
Derivative [Line Items]
Notional Amount	52	66
Unrealized Gain (Loss)	6	2
NOK / SEK
Derivative [Line Items]
Notional Amount	1,053	1,547
Unrealized Gain (Loss)	$ (3)	$ 19