Note 4 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Recorded investment with no related allowance recorded	$ 8,591	$ 9,111
Unpaid principal balance with no related allowance recorded	10,543	11,053
Recorded investment with related allowance recorded	1,361	1,288
Unpaid principal balance with related allowance recorded	1,363	1,289
Related allowance	318	324
Recorded investment	9,952	10,399
Unpaid principle balance	11,906	12,342
Commercial Portfolio Segment [Member]
Recorded investment with no related allowance recorded	71	94
Unpaid principal balance with no related allowance recorded	231	251
Recorded investment with related allowance recorded	560	562
Unpaid principal balance with related allowance recorded	561	563
Related allowance	160	159
Recorded investment	631	656
Unpaid principle balance	792	814
Commercial Real Estate Portfolio Segment [Member]
Related allowance
Recorded investment	3,103	3,103
Unpaid principle balance	3,103	3,103
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member]
Recorded investment with no related allowance recorded	3,103	3,103
Unpaid principal balance with no related allowance recorded	3,103	3,103
Residential Portfolio Segment [Member]
Related allowance	148	154
Recorded investment	6,179	6,600
Unpaid principle balance	7,972	8,385
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Individual Tax Identification Number Loan [Member]
Recorded investment with no related allowance recorded	5,233	5,723
Unpaid principal balance with no related allowance recorded	6,899	7,386
Recorded investment with related allowance recorded	536	455
Unpaid principal balance with related allowance recorded	537	455
Related allowance	35	38
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Mortgage Receivable [Member]
Recorded investment with no related allowance recorded	184	191
Unpaid principal balance with no related allowance recorded	310	313
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Recorded investment with no related allowance recorded		231
Unpaid principal balance with no related allowance recorded		231
Recorded investment with related allowance recorded	226
Unpaid principal balance with related allowance recorded	226
Related allowance	113
Consumer Portfolio Segment [Member]
Recorded investment with related allowance recorded	39	40
Unpaid principal balance with related allowance recorded	39	40
Related allowance	10	11
Recorded investment	39	40
Unpaid principle balance	$ 39	$ 40

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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