Note 3 - Cash, Cash Equivalents and Short-term Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Cash	$ 6,128	$ 4,092
Cash equivalents (see detail in Note 4)	5,854	3,620
Restricted cash	600	600
Total cash and cash equivalents	12,582	8,312	$ 6,933	$ 10,531
Short-term investments (see detail in Note 4)		2,249
Total cash, cash equivalents and short-term investments	$ 12,582	$ 10,561

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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