Note 14 - Stockholders' Equity (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Feb. 09, 2016	Feb. 11, 2015
Stock Buyback Program 2015 [Member]
Stock Repurchase Program, Authorized Amount			$ 40,000,000	$ 20,000,000
Stock Repurchased and Retired During Period, Shares	98,718	214,089
Stock Repurchased and Retired During Period, Value	$ 2,200,000	$ 4,100,000
Tender Offer [Member]
Stock Repurchased and Retired During Period, Shares		193,907
Stock Repurchased and Retired During Period, Value		$ 3,600,000
Treasury Stock Acquired, Average Cost Per Share		$ 18.50
Stock Repurchased Transaction Costs		$ 70,000
Stock Repurchased and Retired During Period, Value	$ 2,180,279