Note 2 - Significant Accounting Policies and Basis of Presentation - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue	$ 778	$ 2,471	$ 2,452	$ 3,999
Software and Royalties [Member]
Revenue	40	587	301	780
Hardware and Consumables [Member]
Revenue	20	13	76	75
Service [Member]
Revenue	85	1,258	98	1,274
Maintenance [Member]
Revenue	$ 633	$ 613	$ 1,977	$ 1,870