Note 6 - Derivative Instruments - Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) (Details) - Cash Flow Hedging [Member] - Designated as Hedging Instrument [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Foreign Exchange Forward [Member]
Derivative, Pre-tax gain (loss) recognized in OCI	$ (167)	$ (167)
Interest Rate Swap [Member]
Derivative, Pre-tax gain (loss) recognized in OCI	$ 453	$ 2,732