Note 5 - Derivative Instruments and Hedging Activities - Fair Value Adjustments of Forward Currency Forward Contracts Not Designated as Hedges (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Gain (loss) on settlement	$ (441)	$ 79
Foreign Exchange Forward [Member] \| Not Designated as Hedging Instrument [Member]
Gain (loss) on settlement		(39)
Gain (loss) on change in fair value		$ 118
Foreign Exchange Forward [Member] \| Not Designated as Hedging Instrument [Member] \| Maximum [Member]
Gain (loss) on settlement	(93)
Gain (loss) on change in fair value	$ (348)

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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