Note 19 - Income Taxes - Reconciliation of Income Taxes (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income tax at the federal statutory rate	21.00%	21.00%
State franchise tax, net of federal tax benefit	8.60%	8.30%
Amortization of affordable housing credit partnerships	2.40%	2.70%
Officer life insurance	(0.50%)	(0.60%)
Tax-exempt interest	(1.30%)	(1.80%)
Affordable housing credits and benefits	(3.50%)	(3.80%)
Accelerated depreciation - cost segregation study		(2.50%)
Reversal of uncertain tax position		(5.10%)
Other	0.20%	0.50%
Effective Tax Rate	26.90%	18.70%