Note 11 - Other Borrowings and Unused Lines of Credit (Details) - USD ($)		12 Months Ended
	Feb. 12, 2019	Dec. 31, 2018	Dec. 31, 2017
Other borrowings		$ 72,032,318	$ 66,000,000
Interest rate (as a percent)		4.94%	3.82%
Revolving line of credit
Other borrowings		$ 9,000,000
Interest rate (as a percent)		5.02%
London Interbank Offered Rate (LIBOR)
Variable interest rate (as a percent)	282.00%
London Interbank Offered Rate (LIBOR) | Revolving line of credit
Variable interest rate (as a percent)		2.50%
Term Note 1
Other borrowings		$ 18,000,000	$ 24,000,000
Interest rate (as a percent)		5.52%	4.56%
Term Note 1 | London Interbank Offered Rate (LIBOR)
Variable interest rate (as a percent)		3.00%
Term Note 2
Other borrowings		$ 5,300,000	$ 7,000,000
Interest rate (as a percent)		5.52%	4.56%
Term Note 2 | London Interbank Offered Rate (LIBOR)
Variable interest rate (as a percent)		3.00%
Term notes
Other borrowings		$ 23,250,000	$ 31,000,000
Periodic payment of principal amount		$ 1,937,500