Note 3 - Loans - Summary of Loan Classes and an Aging of Past Due Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Total past due	$ 3,145	$ 4,444
Current	571,201	538,412
Loans	574,346	542,856
Non-accrual loans	1,459	3,172
Accruing loans past due 90 days or more amounted	97	235
Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	2,013	1,070
Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	571	534
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	561	2,840
Real Estate 1 [Member] \| Construction and Land Development [Member]
Total past due	166	168
Current	42,998	45,699
Loans	43,164	45,867
Non-accrual loans	367	327
Accruing loans past due 90 days or more amounted	30
Real Estate 1 [Member] \| Construction and Land Development [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due		88
Real Estate 1 [Member] \| Construction and Land Development [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	136	80
Real Estate 1 [Member] \| Construction and Land Development [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	30
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member]
Total past due	1,849	1,563
Current	227,589	214,382
Loans	229,438	215,945
Non-accrual loans	630	663
Accruing loans past due 90 days or more amounted	67
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	1,428	747
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	306	393
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	115	423
Real Estate 1 [Member] \| Other Real Estate Loans [Member]
Total past due	873	2,388
Current	235,682	217,165
Loans	236,555	219,553
Non-accrual loans	462	1,985
Accruing loans past due 90 days or more amounted		222
Real Estate 1 [Member] \| Other Real Estate Loans [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	457	145
Real Estate 1 [Member] \| Other Real Estate Loans [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due		36
Real Estate 1 [Member] \| Other Real Estate Loans [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	416	2,207
Commercial and Industrial Loans [Member]
Total past due	95	235
Current	50,058	44,370
Loans	50,153	44,605
Non-accrual loans		197
Accruing loans past due 90 days or more amounted		13
Commercial and Industrial Loans [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	45
Commercial and Industrial Loans [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	50	25
Commercial and Industrial Loans [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due		210
Consumer and Other Loans [Member]
Total past due	162	90
Current	14,874	16,796
Loans	15,036	16,886
Non-accrual loans
Accruing loans past due 90 days or more amounted
Consumer and Other Loans [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	83	90
Consumer and Other Loans [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	79
Consumer and Other Loans [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due

Amount of financing receivable 90 days or more past due and still accruing.

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