Note 5 - Derivative Instruments and Hedging Activities - Foreign Currency Forward Contracts (Details) $ in Thousands	Mar. 31, 2020 USD ($)
Notional amount of U.S. dollars	$ 61,751
Weighted average exchange rate of U.S. dollars	1.3795
Foreign currency forward contracts, liability	$ (1,176)
Foreign Exchange Forward 1 [Member]
Notional amount of U.S. dollars	$ 9,653
Weighted average exchange rate of U.S. dollars	1.3296
Foreign currency forward contracts, liability	$ (526)
Foreign Exchange Forward 2 [Member]
Notional amount of U.S. dollars	$ 10,656
Weighted average exchange rate of U.S. dollars	1.3227
Foreign currency forward contracts, liability	$ (627)
Foreign Exchange Forward 3 [Member]
Notional amount of U.S. dollars	$ 9,658
Weighted average exchange rate of U.S. dollars	1.3227
Foreign currency forward contracts, liability	$ (565)
Foreign Exchange Forward 4 [Member]
Notional amount of U.S. dollars	$ 11,124
Weighted average exchange rate of U.S. dollars	1.4283
Foreign currency forward contracts, asset	$ 172
Foreign Exchange Forward 5 [Member]
Notional amount of U.S. dollars	$ 9,878
Weighted average exchange rate of U.S. dollars	1.4283
Foreign currency forward contracts, asset	$ 150
Foreign Exchange Forward 6 [Member]
Notional amount of U.S. dollars	$ 10,782
Weighted average exchange rate of U.S. dollars	1.4362
Foreign currency forward contracts, asset	$ 220