Note 2 - Summary of Significant Accounting Policies - Weighted Average Common Shares (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Weighted average common shares outstanding - basic (in shares)	10,277,155	10,295,836	10,270,860	10,342,919
Potentially dilutive securities:
Unvested shares of restricted stock and stock options (in shares)	57,739	14,856	44,255	14,549
Weighted average common shares and common share equivalents outstanding - diluted (in shares)	10,334,894	10,310,692	10,315,115	10,357,468
Average number of potentially dilutive securities excluded from calculation (in shares)	96,000	19,800	71,630	17,516