Note 3 - Loans - Summary of Loan Classes and an Aging of Past Due Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Total past due	$ 1,913	$ 4,444
Current	573,041	538,412
Loans	574,954	542,856	$ 530,933
Non-accrual loans	1,775	3,172
Accruing loans past due 90 days or more amounted	19	235
Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	883	1,070
Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	155	534
Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	875	2,840
Real Estate 1 [Member] \| Construction and Land Development [Member]
Total past due	80	168
Current	46,201	45,699
Loans	46,281	45,867	37,350
Non-accrual loans	391	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		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	80
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member]
Total past due	1,028	1,563
Current	224,792	214,382
Loans	225,820	215,945	211,101
Non-accrual loans	866	663
Accruing loans past due 90 days or more amounted
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	580	747
Real Estate 1 [Member] \| Secured by Multi-family Residential Properties [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	140	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	308	423
Real Estate 1 [Member] \| Other Real Estate Loans [Member]
Total past due	660	2,388
Current	236,710	217,165
Loans	237,370	219,553	224,362
Non-accrual loans	518	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	192	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	468	2,207
Commercial and Industrial Loans [Member]
Total past due	35	235
Current	49,318	44,370
Loans	49,353	44,605	40,943
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	35
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	110	90
Current	16,020	16,796
Loans	16,130	16,886	$ 17,177
Non-accrual loans
Accruing loans past due 90 days or more amounted	19
Consumer and Other Loans [Member] \| Financial Asset, 30 to 59 Days Past Due [Member]
Total past due	76	90
Consumer and Other Loans [Member] \| Financial Asset, 60 to 89 Days Past Due [Member]
Total past due	15
Consumer and Other Loans [Member] \| Financial Asset, Equal to or Greater than 90 Days Past Due [Member]
Total past due	$ 19

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

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