Note 3 - Cash, Cash Equivalents and Restricted Cash - Schedule of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Cash	$ 5,411	$ 2,506
Cash equivalents (see detail in Note 4)	33,810	37,023
Restricted cash	220	557
Total cash and cash equivalents	$ 39,441	$ 40,086	$ 10,365	$ 12,960

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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