Note 15 - Share Repurchase Program (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2016	Mar. 31, 2015	Nov. 30, 2013
Stock Repurchase Program, Authorized Amount		$ 75	$ 35
Stock Repurchased During Period, Shares	317,493
Stock Repurchased During Period, Value	$ 11,900,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 37,700,000