Note 1 - Nature of Operations, Basis of Presentation and Company Conditions - Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands		Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Cash and cash equivalents at beginning of period		$ 23,993	$ 21,489	$ 20,949	$ 26,865
Restricted cash at beginning of period (1)	[1]	699	609	1,172	1,176
Cash, cash equivalents and restricted cash at beginning of period		$ 24,692	$ 22,098	$ 22,121	$ 28,041

[1] Restrictions on cash at March 31, 2023 and March 31, 2022 relate to collateral for several bank-issued letters of credit for contract guaranties.