Note 6 - Financial Instruments and Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Gain (Loss) from Components Excluded from Assessment of Cash Flow Hedge Effectiveness, Net, Total	$ 0
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	300
Foreign Currency Transaction Gain (Loss), before Tax, Total	$ 656	$ (451)

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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The net gain (loss) relating to components of the gain (loss) on the cash flow hedging instrument excluded from the assessment of cash flow hedge effectiveness. Recognized in earnings.

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