Note 2 - Revenue Recognition - Timing of Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Revenues	$ 24,261	$ 22,550
Transferred at Point in Time [Member]
Revenues	20,072	15,787
Transferred over Time [Member]
Revenues	$ 4,189	$ 6,763