Note 4 - Loans - Impaired Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Recorded investment with no related allowance recorded	$ 11,410	$ 9,111
Unpaid principal balance with no related allowance recorded	13,569	11,053
Recorded investment with related allowance recorded	947	1,288
Unpaid principal balance with related allowance recorded	947	1,289
Related allowance	204	324
Recorded investment	12,357	10,399
Unpaid principle balance	14,516	12,342
Commercial Portfolio Segment [Member]
Recorded investment with no related allowance recorded	1,458	94
Unpaid principal balance with no related allowance recorded	1,811	251
Recorded investment with related allowance recorded	622	562
Unpaid principal balance with related allowance recorded	622	563
Related allowance	122	159
Recorded investment	2,080	656
Unpaid principle balance	2,433	814
Commercial Real Estate Portfolio Segment [Member]
Related allowance	0	0
Recorded investment	4,812	3,103
Unpaid principle balance	4,962	3,103
Commercial Real Estate Portfolio Segment [Member] \| Commercial Non-owner Occupied [Member]
Recorded investment with no related allowance recorded	1,062
Unpaid principal balance with no related allowance recorded	1,097
Commercial Real Estate Portfolio Segment [Member] \| Commercial Owner Occupied Loan [Member]
Recorded investment with no related allowance recorded	3,750	3,103
Unpaid principal balance with no related allowance recorded	3,865	3,103
Residential Portfolio Segment [Member]
Related allowance	77	154
Recorded investment	5,447	6,600
Unpaid principle balance	7,103	8,385
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Individual Tax Identification Number Loan [Member]
Recorded investment with no related allowance recorded	4,995	5,723
Unpaid principal balance with no related allowance recorded	6,591	7,386
Recorded investment with related allowance recorded	176	455
Unpaid principal balance with related allowance recorded	176	455
Related allowance	12	38
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Mortgage Receivable [Member]
Recorded investment with no related allowance recorded	145	191
Unpaid principal balance with no related allowance recorded	205	313
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Recorded investment with related allowance recorded	131	231
Unpaid principal balance with related allowance recorded	131	231
Related allowance	65	116
Consumer Portfolio Segment [Member]
Recorded investment with related allowance recorded	18	40
Unpaid principal balance with related allowance recorded	18	40
Related allowance	5	11
Recorded investment	18	40
Unpaid principle balance	$ 18	$ 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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