Note 14 - Employee Benefit Plans - Profit Sharing Contributions (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Matching contribution	$ 1,663,198	$ 1,365,111	$ 1,314,276
	$ 1,663,198	$ 1,365,111	$ 1,314,276