Note 4 - Loan Receivables and Allowance for Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2019
Balance	$ 10,115	$ 7,609	$ 6,297
Charge-offs	(1,778)	(2,659)	(35)
Recoveries	77	194	44
Provisions (credits)	2,170	4,971	1,303
Balance	10,584	10,115	7,609
Total allowance for loan and lease losses	10,584	7,609	6,297	$ 10,584	$ 10,115
Business Activities Loans [Member]
Balance	10,115
Balance	10,584	10,115
Allowance for loan losses: Individually evaluated for impairment				1,412	1,496
Allowance for loan losses: Collectively evaluated for impairment				9,172	8,619
Total allowance for loan and lease losses	10,115	10,115		10,584	10,115
Loans receivable, gross: Individually evaluated for impairment				24,383	19,628
Loans receivable, gross: Collectively evaluated for impairment				705,797	792,360
Total loans receivable, gross				730,180	812,164
PCI loans individually evaluated for impairment					176
Commercial Real Estate Portfolio Segment [Member]
Balance	3,789	1,866	2,212
Charge-offs	(1,032)	0
Recoveries		2	7
Provisions (credits)	1,728	1,921	(353)
Balance	4,485	3,789	1,866
Total allowance for loan and lease losses	4,485	1,866	2,212	4,485	3,789
Commercial Real Estate Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	3,789
Balance	4,485	3,789
Allowance for loan losses: Individually evaluated for impairment				1,398	1,496
Allowance for loan losses: Collectively evaluated for impairment				3,087	2,293
Total allowance for loan and lease losses	3,789	3,789		4,485	3,789
Loans receivable, gross: Individually evaluated for impairment				14,534	13,034
Loans receivable, gross: Collectively evaluated for impairment				267,844	301,380
Total loans receivable, gross				282,378	314,414
PCI loans individually evaluated for impairment
Residential Portfolio Segment [Member]
Balance	1,038	1,059	959
Charge-offs	(24)	(118)	(2)
Recoveries	1	10	2
Provisions (credits)	364	87	100
Balance	1,379	1,038	1,059
Total allowance for loan and lease losses	1,379	1,059	959	1,379	1,038
Residential Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	1,038
Balance	1,379	1,038
Allowance for loan losses: Individually evaluated for impairment				4
Allowance for loan losses: Collectively evaluated for impairment				1,375	1,038
Total allowance for loan and lease losses	1,038	1,038		1,379	1,038
Loans receivable, gross: Individually evaluated for impairment				3,962	3,621
Loans receivable, gross: Collectively evaluated for impairment				149,889	171,868
Total loans receivable, gross				153,851	175,489
PCI loans individually evaluated for impairment
Commercial Portfolio Segment [Member]
Balance	4,340	3,558	2,023
Charge-offs	(677)	(2,418)
Recoveries	70	172	34
Provisions (credits)	(449)	3,028	1,501
Balance	3,284	4,340	3,558
Total allowance for loan and lease losses	3,284	3,558	2,023	3,284	4,340
Commercial Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	4,340
Balance	3,284	4,340
Allowance for loan losses: Individually evaluated for impairment
Allowance for loan losses: Collectively evaluated for impairment				3,284	4,340
Total allowance for loan and lease losses	4,340	4,340		3,284	4,340
Loans receivable, gross: Individually evaluated for impairment				4,700	2,057
Loans receivable, gross: Collectively evaluated for impairment				139,597	171,642
Total loans receivable, gross				144,297	173,875
PCI loans individually evaluated for impairment					176
Consumer Portfolio Segment [Member]
Balance	341	641	568
Charge-offs	(45)	(123)	(33)
Recoveries	6	10	1
Provisions (credits)	(7)	(187)	105
Balance	295	341	641
Total allowance for loan and lease losses	295	641	568	295	341
Consumer Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	341
Balance	295	341
Allowance for loan losses: Individually evaluated for impairment				10
Allowance for loan losses: Collectively evaluated for impairment				285	341
Total allowance for loan and lease losses	341	341		295	341
Loans receivable, gross: Individually evaluated for impairment				1,187	916
Loans receivable, gross: Collectively evaluated for impairment				66,448	85,018
Total loans receivable, gross				67,635	85,934
PCI loans individually evaluated for impairment
Construction Portfolio Segment [Member]
Balance	477	350	481
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	262	127	(131)
Balance	739	477	350
Total allowance for loan and lease losses	739	350	481	739	477
Construction Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	477
Balance	739	477
Allowance for loan losses: Individually evaluated for impairment				0	0
Allowance for loan losses: Collectively evaluated for impairment				739	477
Total allowance for loan and lease losses	477	477		739	477
Loans receivable, gross: Individually evaluated for impairment
Loans receivable, gross: Collectively evaluated for impairment				66,984	48,388
Total loans receivable, gross				66,984	48,388
PCI loans individually evaluated for impairment
Construction to Permanent Portfolio Segment [Member]
Balance	130	108	54
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	32	22	54
Balance	162	130	108
Total allowance for loan and lease losses	162	108	54	162	130
Construction to Permanent Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	130
Balance	162	130
Allowance for loan losses: Individually evaluated for impairment				0	0
Allowance for loan losses: Collectively evaluated for impairment				162	130
Total allowance for loan and lease losses	130	130		162	130
Loans receivable, gross: Individually evaluated for impairment				0	0
Loans receivable, gross: Collectively evaluated for impairment				15,035	14,064
Total loans receivable, gross				15,035	14,064
PCI loans individually evaluated for impairment
Unallocated Financing Receivables [Member]
Balance		27
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	240	(27)	27
Balance	240		27
Total allowance for loan and lease losses	240	27		240
Unallocated Financing Receivables [Member] \| Business Activities Loans [Member]
Balance
Balance	240
Allowance for loan losses: Individually evaluated for impairment				0	0
Allowance for loan losses: Collectively evaluated for impairment				240
Total allowance for loan and lease losses				240
Loans receivable, gross: Individually evaluated for impairment				0	0
Loans receivable, gross: Collectively evaluated for impairment
Total loans receivable, gross
PCI loans individually evaluated for impairment

The amount of acquired loans that were individually evaluated for impairment.

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

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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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 before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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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