Note 2 - Common Stock Outstanding and Earnings Per Share - Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended
		Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019
Net income		$ 916	$ 4,369	$ 4,642	$ 3,644	$ 2,306
Weighted average shares - basic (in shares)	[1]	17,695				17,489
Effect of potentially dilutive common shares (in shares)	[2]	52				63
Weighted average number of common shares outstanding - diluted (in shares)		17,747				17,552
Earnings per share - basic (in dollars per share)		$ 0.05				$ 0.13
Earnings per share - diluted (in dollars per share)		$ 0.05				$ 0.13
Share-based Payment Arrangement, Option [Member]
Anti-dilutive options not included in diluted earnings per share calculation (in shares)
Restricted Stock [Member]
Anti-dilutive options not included in diluted earnings per share calculation (in shares)

[1] Excludes unvested restricted shares because they do not have dividend or voting rights

[2] Represents the effects of the assumed exercise of stock options and vesting of non-participating restricted shares.