Note 3 - Earnings Per Share - Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Net loss										$ (1,487)	$ (4,523)
Weighted average number of common shares outstanding (in shares)										16,745,531	16,127,296
Basic (in dollars per share)		$ (0.12)	$ (0.06)	$ 0.03	$ 0.06	$ (0.09)	$ (0.06)	$ (0.06)	$ (0.07)	$ (0.09)	$ (0.28)
Non-vested stock awards (in shares)	[1]
Weighted average number of common shares outstanding (in shares)										16,745,531	16,127,296
Diluted (in dollars per share)		$ (0.12)	$ (0.06)	$ 0.03	$ 0.06	$ (0.09)	$ (0.06)	$ (0.06)	$ (0.07)	$ (0.09)	$ (0.28)

[1] Stock options and restricted stock units granted and outstanding of 1,332,884 and 1,411,277, respectively, are excluded from the computation of diluted earnings for the years ended December 31, 2020 and 2019 due to the anti-dilutive effect as a result of the Company's net loss for those respective periods.