Note 2 - Loans and Allowance for Loan Losses - Loan Portfolio by Risk Rating (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Loans, gross	$ 2,344,505	$ 2,330,600	$ 2,169,687
Pass [Member]
Loans, gross	2,336,528	2,322,354
Special Mention [Member]
Loans, gross	3,135	3,639
Substandard [Member]
Loans, gross	4,842	4,607
Doubtful [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member]
Loans, gross	2,096,903	2,076,783
Real Estate Portfolio Segment [Member] | Residential 1 to 4 Family [Member]
Loans, gross	527,092	535,994	519,775
Real Estate Portfolio Segment [Member] | Residential 1 to 4 Family [Member] | Pass [Member]
Loans, gross	520,890	529,546
Real Estate Portfolio Segment [Member] | Residential 1 to 4 Family [Member] | Special Mention [Member]
Loans, gross	2,207	2,745
Real Estate Portfolio Segment [Member] | Residential 1 to 4 Family [Member] | Substandard [Member]
Loans, gross	3,995	3,703
Real Estate Portfolio Segment [Member] | Residential 1 to 4 Family [Member] | Doubtful [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member]
Loans, gross	93,318	111,646	151,929
Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] | Pass [Member]
Loans, gross	93,318	111,646
Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] | Special Mention [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] | Substandard [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] | Doubtful [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member]
Loans, gross	865,388	837,766	841,521
Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Pass [Member]
Loans, gross	864,802	837,028
Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Special Mention [Member]
Loans, gross	0	149
Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Substandard [Member]
Loans, gross	586	589
Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] | Doubtful [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans, gross	513,931	488,626	388,769
Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Pass [Member]
Loans, gross	513,383	488,571
Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Special Mention [Member]
Loans, gross	548	27
Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Substandard [Member]
Loans, gross	0	28
Real Estate Portfolio Segment [Member] | Construction Loans [Member] | Doubtful [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member] | Farmland [Member]
Loans, gross	12,377	15,429	18,610
Real Estate Portfolio Segment [Member] | Farmland [Member] | Pass [Member]
Loans, gross	12,257	15,301
Real Estate Portfolio Segment [Member] | Farmland [Member] | Special Mention [Member]
Loans, gross	76	79
Real Estate Portfolio Segment [Member] | Farmland [Member] | Substandard [Member]
Loans, gross	44	49
Real Estate Portfolio Segment [Member] | Farmland [Member] | Doubtful [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member] | Second Mortgages [Member]
Loans, gross	8,164	8,433	11,254
Real Estate Portfolio Segment [Member] | Second Mortgages [Member] | Pass [Member]
Loans, gross	7,886	8,148
Real Estate Portfolio Segment [Member] | Second Mortgages [Member] | Special Mention [Member]
Loans, gross	166	169
Real Estate Portfolio Segment [Member] | Second Mortgages [Member] | Substandard [Member]
Loans, gross	112	116
Real Estate Portfolio Segment [Member] | Second Mortgages [Member] | Doubtful [Member]
Loans, gross	0	0
Real Estate Portfolio Segment [Member] | Home Equity Line of Credit [Member]
Loans, gross	76,633	78,889	74,908
Real Estate Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Pass [Member]
Loans, gross	76,612	78,565
Real Estate Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Special Mention [Member]
Loans, gross	11	314
Real Estate Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Substandard [Member]
Loans, gross	10	10
Real Estate Portfolio Segment [Member] | Home Equity Line of Credit [Member] | Doubtful [Member]
Loans, gross	0	0
Commercial Portfolio Segment [Member]
Loans, gross	170,712	172,811	95,547
Commercial Portfolio Segment [Member] | Pass [Member]
Loans, gross	170,684	172,779
Commercial Portfolio Segment [Member] | Special Mention [Member]
Loans, gross	0	0
Commercial Portfolio Segment [Member] | Substandard [Member]
Loans, gross	28	32
Commercial Portfolio Segment [Member] | Doubtful [Member]
Loans, gross	0	0
Agricultural Installment and Other Portfolio Segment [Member]
Loans, gross	76,890	81,006	$ 67,374
Agricultural Installment and Other Portfolio Segment [Member] | Pass [Member]
Loans, gross	76,696	80,770
Agricultural Installment and Other Portfolio Segment [Member] | Special Mention [Member]
Loans, gross	127	156
Agricultural Installment and Other Portfolio Segment [Member] | Substandard [Member]
Loans, gross	67	80
Agricultural Installment and Other Portfolio Segment [Member] | Doubtful [Member]
Loans, gross	$ 0	$ 0