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		12 Months Ended
		Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Net income		$ 3,241	$ 2,252	$ 7,344
Weighted average shares - basic (in shares)	[1]	16,225	13,416
Effect of potentially dilutive common shares (2) (in shares)	[2]	85	105
Weighted average number of common shares outstanding - diluted (in shares)		16,310	13,521
Earnings per share - basic (in dollars per share)		$ 0.20	$ 0.17
Earnings per share - diluted (in dollars per share)		$ 0.20	$ 0.17
Equity 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)		41,915	33,068

[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.