Note 4 - Fair Values of Financial Instruments - Schedule of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Reported Value Measurement [Member]
Financial Assets:
Cash and cash equivalents	$ 5,532	$ 6,951
Accounts receivable	19,256	10,729
Other current assets - restricted cash	1,333	429
Financial liabilities:
Accounts payable	(10,663)	(16,393)
Debt	(12,947)	(9,474)
Other liabilities - financed insurance payable	(656)	(287)
Estimate of Fair Value Measurement [Member]
Financial Assets:
Cash and cash equivalents	5,532	6,951
Accounts receivable	19,256	10,729
Other current assets - restricted cash	1,333	429
Financial liabilities:
Accounts payable	(10,663)	(16,393)
Debt	(12,947)	(9,474)
Other liabilities - financed insurance payable	$ (656)	$ (287)