Note 3 - Loans - Summary of Loan Classes and an Aging of Past Due Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Total past due	$ 1,724	$ 4,444
Current	569,529	538,412
Loans	571,253	542,856	$ 539,821
Non-accrual loans	1,566	3,172
Accruing loans past due 90 days or more amounted	113	235
Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	819	1,070
Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	278	534
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	627	2,840
Real Estate 1 [Member] \| Construction and Land Development [Member]
Total past due	50	168
Current	45,143	45,699
Loans	45,193	45,867	42,982
Non-accrual loans	376	327
Accruing loans past due 90 days or more amounted
Real Estate 1 [Member] \| Construction and Land Development [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	50	88
Real Estate 1 [Member] \| Construction and Land Development [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due		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
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member]
Total past due	1,021	1,563
Current	225,807	214,382
Loans	226,828	215,945	211,938
Non-accrual loans	690	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	612	747
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	253	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	156	423
Real Estate 1 [Member] \| Other Real Estate Loans [Member]
Total past due	474	2,388
Current	232,593	217,165
Loans	233,067	219,553	224,903
Non-accrual loans	500	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	49	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	425	2,207
Commercial and Industrial Loans [Member]
Total past due	46	235
Current	50,511	44,370
Loans	50,557	44,605	42,861
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	46
Commercial and Industrial Loans [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due		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	133	90
Current	15,475	16,796
Loans	15,608	16,886	$ 17,137
Non-accrual loans
Accruing loans past due 90 days or more amounted	46
Consumer and Other Loans [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	62	90
Consumer and Other Loans [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	25
Consumer and Other Loans [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	$ 46

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

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