Derivatives Notional Amounts - Designated as Hedges (Details) - Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Derivative [Line Items]
Notional Amount	$ 128,209	$ 164,358
Unrealized Gain (Loss)	1,407	776
USD / AUD
Derivative [Line Items]
Notional Amount	4,467	5,841
Unrealized Gain (Loss)	(19)	316
USD / CAD
Derivative [Line Items]
Notional Amount	1,943	2,604
Unrealized Gain (Loss)	5	(18)
USD / CNY
Derivative [Line Items]
Notional Amount	7,744	11,252
Unrealized Gain (Loss)	(158)	(301)
USD / CHF
Derivative [Line Items]
Notional Amount	270	370
Unrealized Gain (Loss)	9	15
USD / EUR
Derivative [Line Items]
Notional Amount	58,476	60,387
Unrealized Gain (Loss)	1,781	1,826
USD / GBP
Derivative [Line Items]
Notional Amount	2,720	3,253
Unrealized Gain (Loss)	(29)	(75)
USD / NZD
Derivative [Line Items]
Notional Amount	9,230	9,650
Unrealized Gain (Loss)	21	(64)
USD / SEK
Derivative [Line Items]
Notional Amount	3,037	4,923
Unrealized Gain (Loss)	47	146
USD / MXP
Derivative [Line Items]
Notional Amount	4,591	6,148
Unrealized Gain (Loss)	186	(417)
EUR / AUD
Derivative [Line Items]
Notional Amount	403	506
Unrealized Gain (Loss)	(16)	6
EUR / GBP
Derivative [Line Items]
Notional Amount	20,605	14,511
Unrealized Gain (Loss)	(473)	(686)
EUR / NOK
Derivative [Line Items]
Notional Amount	2,069	2,503
Unrealized Gain (Loss)	(63)	(25)
EUR / NZD
Derivative [Line Items]
Notional Amount	2,859	3,777
Unrealized Gain (Loss)	23	16
GBP / AUD
Derivative [Line Items]
Notional Amount	400	503
Unrealized Gain (Loss)	8	34
GBP / CHF
Derivative [Line Items]
Notional Amount	220	215
Unrealized Gain (Loss)	(4)	(10)
GBP / SEK
Derivative [Line Items]
Notional Amount	2,457	1,389
Unrealized Gain (Loss)	(1)	(42)
CHF / DKK
Derivative [Line Items]
Notional Amount	461	595
Unrealized Gain (Loss)	(7)	(2)
DKK / SEK
Derivative [Line Items]
Notional Amount	3,263	31,978
Unrealized Gain (Loss)	100	49
NOK / CHF
Derivative [Line Items]
Notional Amount	1,018	1,335
Unrealized Gain (Loss)	(20)	(13)
NOK / SEK
Derivative [Line Items]
Notional Amount	1,976	2,618
Unrealized Gain (Loss)	$ 17	$ 21