Note 15 - Stock-Based Compensation (Details) - Stock Purchase Plan (Employee Stock Purchase Plan [Member], USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee Stock Purchase Plan [Member]
Note 15 - Stock-Based Compensation (Details) - Stock Purchase Plan [Line Items]
Shares granted	24,811	27,415	29,671
Shares purchased	25,321	27,110	31,554
Weighted average fair value per share granted (in Dollars per share)	$ 2.37	$ 2.10	$ 1.71