Note 2 - Revenue Recognition - Significant Changes in Contract Assets and Deferred Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Balance at beginning of period	$ 0	$ 46
Revenue recognized	132	16
Amounts invoiced	(45)	(45)
Reclassifications and other	51	0
Balance at end of period	138	17
Balance at beginning of period	210	1,138
Revenue recognized	(154)	(269)
Amounts collected or invoiced	80	295
Reclassifications and other	50	0
Balance at end of period	$ 186	$ 1,164