Note 18 - Financial Instruments - Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Cash and cash equivalents (notes 3 and 4)	$ 32,414	$ 28,520
Short-term investments (notes 3 and 5)	6,172	17,601
LONG-TERM INVESTMENTS (notes 3 and 8)	10,445	3,112
Reported Value Measurement [Member]
Cash and cash equivalents (notes 3 and 4)	32,414	28,520
Restricted cash	34	35
Short-term investments (notes 3 and 5)	6,172	17,601
LONG-TERM INVESTMENTS (notes 3 and 8)	10,445	3,112
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents (notes 3 and 4)	32,414	28,520
Restricted cash	34	35
Short-term investments (notes 3 and 5)	6,172	17,601
LONG-TERM INVESTMENTS (notes 3 and 8)	$ 10,445	$ 3,112

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. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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