Note 4 - Loan Receivables and Allowance for Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Dec. 31, 2020
Balance	$ 10,584	$ 10,115
Charge-offs	(272)	(44)
Recoveries	114	41
Provisions (credits)		804
Balance	10,426	10,916
Total allowance for loan and lease losses	10,584	10,916	$ 10,426	$ 10,584
Total loans receivable, gross			676,676	730,180
Business Activities Loans [Member]
Balance	10,584
Balance	10,426
Allowance for loan losses: Individually evaluated for impairment			1,919	1,412
Allowance for loan losses: Collectively evaluated for impairment			8,507	9,172
Total allowance for loan and lease losses	10,584		10,426	10,584
Loans receivable, gross: Individually evaluated for impairment			28,457	24,383
Loans receivable, gross: Collectively evaluated for impairment			648,219	705,797
Total loans receivable, gross			676,676	730,180
Commercial Real Estate Portfolio Segment [Member]
Balance	4,485	3,789
Charge-offs	(42)	0
Recoveries
Provisions (credits)	(289)	361
Balance	4,154	4,150
Total allowance for loan and lease losses	4,154	4,150	4,154	4,485
Total loans receivable, gross			261,461	282,378
Commercial Real Estate Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	4,485
Balance	4,154
Allowance for loan losses: Individually evaluated for impairment			1,414	1,398
Allowance for loan losses: Collectively evaluated for impairment			2,740	3,087
Total allowance for loan and lease losses	4,485		4,154	4,485
Loans receivable, gross: Individually evaluated for impairment			17,025	14,534
Loans receivable, gross: Collectively evaluated for impairment			244,436	267,844
Total loans receivable, gross			261,461	282,378
Residential Portfolio Segment [Member]
Balance	1,379	1,038
Charge-offs	(3)	(1)
Recoveries
Provisions (credits)	533	83
Balance	1,909	1,120
Total allowance for loan and lease losses	1,909	1,120	1,909	1,379
Total loans receivable, gross			147,947	153,851
Residential Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	1,379
Balance	1,909
Allowance for loan losses: Individually evaluated for impairment			4	4
Allowance for loan losses: Collectively evaluated for impairment			1,905	1,375
Total allowance for loan and lease losses	1,379		1,909	1,379
Loans receivable, gross: Individually evaluated for impairment			4,247	3,962
Loans receivable, gross: Collectively evaluated for impairment			143,700	149,889
Total loans receivable, gross			147,947	153,851
Commercial Portfolio Segment [Member]
Balance	3,284	4,340
Charge-offs	(209)	(4)
Recoveries	12	40
Provisions (credits)	537	14
Balance	3,624	4,390
Total allowance for loan and lease losses	3,624	4,390	3,624	3,284
Total loans receivable, gross			138,966	144,297
Commercial Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	3,284
Balance	3,624
Allowance for loan losses: Individually evaluated for impairment			501
Allowance for loan losses: Collectively evaluated for impairment			3,123	3,284
Total allowance for loan and lease losses	3,284		3,624	3,284
Loans receivable, gross: Individually evaluated for impairment			6,532	4,700
Loans receivable, gross: Collectively evaluated for impairment			132,434	139,597
Total loans receivable, gross			138,966	144,297
Consumer Portfolio Segment [Member]
Balance	295	341
Charge-offs	(18)	(39)
Recoveries	102	1
Provisions (credits)	3	231
Balance	382	534
Total allowance for loan and lease losses	382	534	382	295
Total loans receivable, gross			56,485	67,635
Consumer Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	295
Balance	382
Allowance for loan losses: Individually evaluated for impairment				10
Allowance for loan losses: Collectively evaluated for impairment			382	285
Total allowance for loan and lease losses	295		382	295
Loans receivable, gross: Individually evaluated for impairment			653	1,187
Loans receivable, gross: Collectively evaluated for impairment			55,832	66,448
Total loans receivable, gross			56,485	67,635
Construction Portfolio Segment [Member]
Balance	739	477
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	(459)	126
Balance	280	603
Total allowance for loan and lease losses	280	603	280	739
Total loans receivable, gross			55,523	66,984
Construction Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	739
Balance	280
Allowance for loan losses: Individually evaluated for impairment			0	0
Allowance for loan losses: Collectively evaluated for impairment			280	739
Total allowance for loan and lease losses	739		280	739
Loans receivable, gross: Individually evaluated for impairment
Loans receivable, gross: Collectively evaluated for impairment			55,523	66,984
Total loans receivable, gross			55,523	66,984
Construction to Permanent Portfolio Segment [Member]
Balance	162	130
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	(85)	(11)
Balance	77	119
Total allowance for loan and lease losses	77	119	77	162
Total loans receivable, gross			16,294	15,035
Construction to Permanent Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	162
Balance	77
Allowance for loan losses: Individually evaluated for impairment			0	0
Allowance for loan losses: Collectively evaluated for impairment			77	162
Total allowance for loan and lease losses	162		77	162
Loans receivable, gross: Individually evaluated for impairment			0	0
Loans receivable, gross: Collectively evaluated for impairment			16,294	15,035
Total loans receivable, gross			16,294	15,035
Unallocated Financing Receivables [Member]
Balance	240
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	(240)
Balance
Total allowance for loan and lease losses				240
Unallocated Financing Receivables [Member] \| Business Activities Loans [Member]
Balance	240
Balance
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			240
Loans receivable, gross: Individually evaluated for impairment			0	0
Loans receivable, gross: Collectively evaluated for impairment
Total loans receivable, gross

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 loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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

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The balance of financing receivables 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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