Financial Instruments - Balance Sheet Location (Details) - Fair Value, Measurements, Recurring [Member] - Fair Value, Inputs, Level 2 [Member] - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Assets [Abstract]
Foreign currency cash flow hedges - asset	$ 665	$ 1,058
Liabilities [Abstract]
Foreign currency cash flow hedges - liability	$ 700	$ 705