Note 15 - Stock-Based Compensation (Details) - Stock Purchase Plan - Employee Stock Purchase Plan [Member] - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Note 15 - Stock-Based Compensation (Details) - Stock Purchase Plan [Line Items]
Shares granted	23,408	24,811	27,415
Shares purchased	24,033	25,321	27,110
Weighted average fair value per share granted (in Dollars per share)	$ 2.39	$ 2.37	$ 2.10