Note 8 - Loans and Related Allowance for Loan and Lease Losses - Nonaccrual Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Loans, current balance	$ 6,690		$ 6,690		$ 8,879
Loans, past due	0		0		0
Beginning balance	10,210	$ 7,304	6,768	$ 7,428
Charge-offs	(3,043)	(438)	(3,758)	(1,051)
Recoveries	192	55	609	194
Provision	4,000	80	7,740	430
Ending balance	11,359	7,001	11,359	7,001
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Loan [Member]
Loans, current balance	1,138		1,138		1,162
Loans, past due	0		0		0
Beginning balance	1,038	866	801	1,315
Charge-offs	0	0	(50)	(31)
Recoveries	1	1	15	3
Provision	64	(30)	337	(450)
Ending balance	1,103	837	1,103	837
Commercial Real Estate Portfolio Segment [Member] \| Non-owner occupied Loan [Member]
Loans, current balance	594		594		3,289
Loans, past due	0		0		0
Beginning balance	5,159	3,588	3,382	2,862
Charge-offs	(3,021)	0	(3,022)	0
Recoveries	0	0	73	0
Provision	3,267	(104)	4,972	622
Ending balance	5,405	3,484	5,405	3,484
Commercial Real Estate Portfolio Segment [Member] \| Multifamily Loan [Member]
Beginning balance	291	412	340	474
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision	55	(23)	6	(85)
Ending balance	346	389	346	389
Residential Portfolio Segment [Member]
Loans, current balance	3,462		3,462		2,576
Loans, past due	0		0		0
Beginning balance	1,167	747	726	761
Charge-offs	0	(360)	(51)	(361)
Recoveries	0	4	30	44
Provision	204	341	666	288
Ending balance	1,371	732	1,371	732
Commercial And Industrial [Member]
Loans, current balance	400		400		946
Loans, past due	0		0		0
Beginning balance	1,105	539	456	969
Charge-offs	(16)	(38)	(185)	(393)
Recoveries	29	16	268	55
Provision	385	(128)	964	(242)
Ending balance	1,503	389	1,503	389
Home Equity Lines of Credit [Member]
Loans, current balance	859		859		709
Loans, past due	0		0		0
Beginning balance	1,203	936	932	820
Charge-offs	0	(18)	(54)	(156)
Recoveries	49	22	65	28
Provision	74	1	383	249
Ending balance	1,326	941	1,326	941
Consumer Portfolio Segment [Member]
Loans, current balance	237		237		197
Loans, past due	0		0		$ 0
Beginning balance	11	119	28	127
Charge-offs	(6)	(22)	(396)	(110)
Recoveries	2	1	12	7
Provision	5	26	368	100
Ending balance	12	124	12	124
Construction and Other [Member]
Beginning balance	236	97	103	100
Charge-offs	0	0	0	0
Recoveries	111	11	146	57
Provision	(54)	(3)	44	(52)
Ending balance	$ 293	$ 105	$ 293	$ 105

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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

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Amount of financing receivable on nonaccrual status.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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