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, 2022	Dec. 31, 2021	Mar. 31, 2021
Cash and cash equivalents at beginning of period		$ 26,865	$ 34,733	$ 3,046
Restricted cash at beginning of period	[1]	1,176	1,179	1,478
Cash, cash equivalents and restricted cash at beginning of period		28,041	35,912	4,524
Cash and cash equivalents at end of period		20,949	26,865	34,733
Restricted cash at end of period	[1]	1,172	1,176	1,179
CASH, CASH EQUIVALENTS AND RESTRICTED CASH AT END OF PERIOD		$ 22,121	$ 28,041	$ 35,912

[1] Restrictions on cash at March 31, 2022 and March 31, 2021 relate to collateral for several bank-issued letters of credit for contract guaranties.