Note 9 - Other Long-term Liabilities (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Amortization of Deferred Revenue	$ 2,812	$ 2,112	$ 7,873	$ 6,191