Note 4 - Loans and Allowance for Credit Losses on Loans - Non-accrual Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Non-accrual with no allowance	$ 1,083	$ 2,067
Non-accrual loans	5,036	12,514
Troubled Debt Restructurings	13	16
Past due 90-days-or-more and still accruing interest	0	649
Home Equity Line of Credit [Member]
Non-accrual with no allowance	0	221
Non-accrual loans	181	221
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	14
Commercial Real Estate Portfolio Segment [Member]
Non-accrual with no allowance	184	1,234
Non-accrual loans	1,440	11,681
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	156
Commercial Real Estate Portfolio Segment [Member] | Non-owner Occupied [Member]
Non-accrual with no allowance	29	186
Non-accrual loans	771	10,278
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	0
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied [Member]
Non-accrual with no allowance	155	1,048
Non-accrual loans	669	1,403
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	156
Commercial and Industrial Portfolio Segment [Member] | Term [Member]
Non-accrual with no allowance	94	6
Non-accrual loans	1,000	6
Troubled Debt Restructurings	13	16
Past due 90-days-or-more and still accruing interest	0	0
Commercial and Industrial Portfolio Segment [Member] | Lines of Credit [Member]
Non-accrual with no allowance	0	88
Non-accrual loans	79	88
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	0
Total Commercial and Industrial Portfolio Segment [Member]
Non-accrual with no allowance	94	94
Non-accrual loans	1,079	94
Troubled Debt Restructurings	13	16
Past due 90-days-or-more and still accruing interest	0	0
Residential Real Estate Portfolio Segment [Member]
Non-accrual with no allowance	805	514
Non-accrual loans	2,212	514
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	479
Residential Real Estate Portfolio Segment [Member] | Non-owner Occupied [Member]
Non-accrual with no allowance	0	101
Non-accrual loans	300	101
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	301
Residential Real Estate Portfolio Segment [Member] | Owner Occupied [Member]
Non-accrual with no allowance	805	413
Non-accrual loans	1,912	413
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	178
Construction and Development [Member]
Non-accrual with no allowance	0	0
Non-accrual loans	0	0
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	0
Consumer Portfolio Segment [Member]
Non-accrual with no allowance	0	4
Non-accrual loans	124	4
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	0
Finance Leases Portfolio Segment [Member]
Non-accrual with no allowance	0	0
Non-accrual loans	0	0
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	0	0
Commercial Portfolio Segment [Member] | Credit Card Receivable [Member]
Non-accrual with no allowance	0	0
Non-accrual loans	0	0
Troubled Debt Restructurings	0	0
Past due 90-days-or-more and still accruing interest	$ 0	$ 0