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							9 Months Ended
		Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Net income		$ 4,329	$ 3,847	$ 916	$ 4,369	$ 4,642	$ 3,644	$ 2,306	$ 9,092	$ 10,592
Weighted average shares - basic (in shares)	[1]	16,660				18,130			17,004	17,918
Effect of potentially dilutive common shares (in shares)	[2]	36				66			40	63
Weighted average number of common shares outstanding - diluted (in shares)		16,696				18,196			17,044	17,981
Earnings per share - basic (in dollars per share)		$ 0.26				$ 0.26			$ 0.53	$ 0.59
Earnings per share - diluted (in dollars per share)		$ 0.26				$ 0.26			$ 0.53	$ 0.59
Restricted Stock [Member]
Anti-dilutive securities not included in earnings per share calculation (in shares)		73				0			63	0

[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.