Note 3 - Loans - Summary of Loan Classes and an Aging of Past Due Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Total past due	$ 1,371	$ 3,145
Current	646,997	571,201
Loans	648,368	574,346
Non-accrual loans	6,974	1,459
Accruing loans past due 90 days or more amounted	6	97
Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	371	2,013
Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	643	571
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	357	561
Real Estate 1 [Member] | Construction and Land Development [Member]
Total past due	133	166
Current	27,339	42,998
Loans	27,472	43,164
Non-accrual loans	283	367
Accruing loans past due 90 days or more amounted	0	30
Real Estate 1 [Member] | Construction and Land Development [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	0	0
Real Estate 1 [Member] | Construction and Land Development [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	133	136
Real Estate 1 [Member] | Construction and Land Development [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	0	30
Real Estate 1 [Member] | Secured by Multi-family Residential Properties [Member]
Total past due	541	1,849
Current	233,657	227,589
Loans	234,198	229,438
Non-accrual loans	469	630
Accruing loans past due 90 days or more amounted	0	67
Real Estate 1 [Member] | Secured by Multi-family Residential Properties [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	172	1,428
Real Estate 1 [Member] | Secured by Multi-family Residential Properties [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	339	306
Real Estate 1 [Member] | Secured by Multi-family Residential Properties [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	30	115
Real Estate 1 [Member] | Other Real Estate Loans [Member]
Total past due	454	873
Current	249,865	235,682
Loans	250,319	236,555
Non-accrual loans	4,674	462
Accruing loans past due 90 days or more amounted	0	0
Real Estate 1 [Member] | Other Real Estate Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	0	457
Real Estate 1 [Member] | Other Real Estate Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	133	0
Real Estate 1 [Member] | Other Real Estate Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	321	416
Commercial and Industrial Loans [Member]
Total past due	96	95
Current	125,181	50,058
Loans	125,277	50,153
Non-accrual loans	1,548	0
Accruing loans past due 90 days or more amounted	0	0
Commercial and Industrial Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	96	45
Commercial and Industrial Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	0	50
Commercial and Industrial Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	0	0
Consumer and Other Loans [Member]
Total past due	147	162
Current	10,955	14,874
Loans	11,102	15,036
Non-accrual loans	0	0
Accruing loans past due 90 days or more amounted	6	0
Consumer and Other Loans [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	103	83
Consumer and Other Loans [Member] | Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	38	79
Consumer and Other Loans [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	$ 6	$ 0