Note 3 - Loans - Risk Category of Loans by Class of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Gross loans	$ 926,271	$ 765,244
Pass [Member]
Gross loans	888,707	745,604
Watch [Member]
Gross loans	27,522	13,164
Special Mention [Member]
Gross loans	0	113
Substandard [Member]
Gross loans	10,042	6,363
Doubtful [Member]
Gross loans	0	0
Commercial Portfolio Segment [Member]
Gross loans	145,551	129,368
Commercial Portfolio Segment [Member] | Pass [Member]
Gross loans	130,312	129,106
Commercial Portfolio Segment [Member] | Watch [Member]
Gross loans	11,280	141
Commercial Portfolio Segment [Member] | Special Mention [Member]
Gross loans	0	0
Commercial Portfolio Segment [Member] | Substandard [Member]
Gross loans	3,959	121
Commercial Portfolio Segment [Member] | Doubtful [Member]
Gross loans	0	0
Commercial Real Estate Portfolio Segment [Member]
Gross loans	399,488	336,981
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Gross loans	64,911	86,867
Commercial Real Estate Portfolio Segment [Member] | Farmland Loans [Member]
Gross loans	79,118	77,937
Commercial Real Estate Portfolio Segment [Member] | Nonfarm Nonresidential [Member]
Gross loans	255,459	172,177
Commercial Real Estate Portfolio Segment [Member] | Pass [Member] | Construction Loans [Member]
Gross loans	64,911	86,867
Commercial Real Estate Portfolio Segment [Member] | Pass [Member] | Farmland Loans [Member]
Gross loans	71,503	74,054
Commercial Real Estate Portfolio Segment [Member] | Pass [Member] | Nonfarm Nonresidential [Member]
Gross loans	245,995	169,551
Commercial Real Estate Portfolio Segment [Member] | Watch [Member] | Construction Loans [Member]
Gross loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Watch [Member] | Farmland Loans [Member]
Gross loans	6,663	2,741
Commercial Real Estate Portfolio Segment [Member] | Watch [Member] | Nonfarm Nonresidential [Member]
Gross loans	6,986	1,983
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member] | Construction Loans [Member]
Gross loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member] | Farmland Loans [Member]
Gross loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member] | Nonfarm Nonresidential [Member]
Gross loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member] | Construction Loans [Member]
Gross loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member] | Farmland Loans [Member]
Gross loans	952	1,142
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member] | Nonfarm Nonresidential [Member]
Gross loans	2,478	643
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member] | Construction Loans [Member]
Gross loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member] | Farmland Loans [Member]
Gross loans	0	0
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member] | Nonfarm Nonresidential [Member]
Gross loans	0	0
Residential Portfolio Segment [Member]
Gross loans	297,579	225,518
Residential Portfolio Segment [Member] | Multifamily Loans [Member]
Gross loans	70,950	49,757
Residential Portfolio Segment [Member] | One- to Four-family Residential Properties [Member]
Gross loans	226,629	175,761
Residential Portfolio Segment [Member] | Pass [Member] | Multifamily Loans [Member]
Gross loans	70,950	44,697
Residential Portfolio Segment [Member] | Pass [Member] | One- to Four-family Residential Properties [Member]
Gross loans	221,727	169,342
Residential Portfolio Segment [Member] | Watch [Member] | Multifamily Loans [Member]
Gross loans	0	5,060
Residential Portfolio Segment [Member] | Watch [Member] | One- to Four-family Residential Properties [Member]
Gross loans	2,420	2,209
Residential Portfolio Segment [Member] | Special Mention [Member] | Multifamily Loans [Member]
Gross loans	0	0
Residential Portfolio Segment [Member] | Special Mention [Member] | One- to Four-family Residential Properties [Member]
Gross loans	0	113
Residential Portfolio Segment [Member] | Substandard [Member] | Multifamily Loans [Member]
Gross loans	0	0
Residential Portfolio Segment [Member] | Substandard [Member] | One- to Four-family Residential Properties [Member]
Gross loans	2,482	4,097
Residential Portfolio Segment [Member] | Doubtful [Member] | Multifamily Loans [Member]
Gross loans	0	0
Residential Portfolio Segment [Member] | Doubtful [Member] | One- to Four-family Residential Properties [Member]
Gross loans	0	0
Consumer Portfolio Segment [Member]
Gross loans	47,790	39,104
Consumer Portfolio Segment [Member] | Pass [Member]
Gross loans	47,657	38,768
Consumer Portfolio Segment [Member] | Watch [Member]
Gross loans	5	11
Consumer Portfolio Segment [Member] | Special Mention [Member]
Gross loans	0	0
Consumer Portfolio Segment [Member] | Substandard [Member]
Gross loans	128	325
Consumer Portfolio Segment [Member] | Doubtful [Member]
Gross loans	0	0
Agriculture Portfolio Segment [Member]
Gross loans	35,064	33,737
Agriculture Portfolio Segment [Member] | Pass [Member]
Gross loans	34,853	32,683
Agriculture Portfolio Segment [Member] | Watch [Member]
Gross loans	168	1,019
Agriculture Portfolio Segment [Member] | Special Mention [Member]
Gross loans	0	0
Agriculture Portfolio Segment [Member] | Substandard [Member]
Gross loans	43	35
Agriculture Portfolio Segment [Member] | Doubtful [Member]
Gross loans	0	0
Other Portfolio Segment [Member]
Gross loans	799	536
Other Portfolio Segment [Member] | Pass [Member]
Gross loans	799	536
Other Portfolio Segment [Member] | Watch [Member]
Gross loans	0	0
Other Portfolio Segment [Member] | Special Mention [Member]
Gross loans	0	0
Other Portfolio Segment [Member] | Substandard [Member]
Gross loans	0	0
Other Portfolio Segment [Member] | Doubtful [Member]
Gross loans	$ 0	$ 0