Derivatives and Hedging - Location of Gains in Consolidated Condensed Statements of Operations that were Recognized and Derivative Contract Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Forward points expensed on derivatives	$ 158		$ 219
Other (expense) income, net
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Net Gain (Loss) Recognized in Income on Derivative Instruments	7,220	$ (1,128)	3,360	$ (6,303)
Foreign Exchange Forward | Cost Of Goods Sold
Derivative Instruments, Gain (Loss) [Line Items]
Gain Reclassified from AOCI into COGS	$ 155	$ 414	$ 200	$ 1,316