Note 7 - Derivatives and Hedging Activities - Significantly Impact of operations (Details) - Interest rate swap - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fee Income On Derivative Contracts	$ 10,800,000	$ 3,100,000	$ 1,700,000
Not Designated as Hedging Instrument [Member]
Derivative Asset, Notional Amount	445,021,807	230,434,728
Derivative Assets	22,195,713	4,397,238
Derivative Liability, Notional Amount	445,021,807	230,434,728
Derivative Liabilities	$ 22,195,713	$ 4,397,238