Note 4 - Revenue Recognition - Costs, Estimated Earnings, and Billings on Uncompleted Contracts (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Costs incurred on contracts in progress	$ 13,229
Estimated earnings	8,832
Costs and Estimated Earnings on Uncompleted Contracts	22,061
Billings to date	(19,492)
Net Cost in Excess of Billings	2,569
Deferred revenue related to non-system contracts	(124)
Contract Liability In Excess of Contract Assets	2,445
Included in accompanying condensed consolidated balance sheets under the following captions (in thousands):
Contract assets	3,706
Contract liabilities	$ 1,261	$ 4,100	$ 1,700