Note 4 - Loan Receivables and Allowance for Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Balance	$ 9,905,000	$ 10,584,000
Charge-offs	(185,000)	(272,000)
Recoveries	17,000	114,000
Provisions (credits)	0	0
Balance	9,737,000	10,426,000
Allowance for loan losses: Individually evaluated for impairment	2,700,000
Allowance for loan losses: Collectively evaluated for impairment	6,000		$ 7,000
Loans receivable, gross: Individually evaluated for impairment	23,600,000
Loans receivable, gross: Collectively evaluated for impairment	521,000		590,000
Total loans receivable, gross	773,339,000		739,488,000
Business Activities Loans [Member]
Balance	9,905,000
Balance	9,737,000
Allowance for loan losses: Individually evaluated for impairment	2,709,000		2,292,000
Allowance for loan losses: Collectively evaluated for impairment	7,028,000		7,613,000
Loans receivable, gross: Individually evaluated for impairment	23,648,000		23,212,000
Loans receivable, gross: Collectively evaluated for impairment	749,691,000		716,276,000
Total loans receivable, gross	773,339,000		739,488,000
Commercial Real Estate Portfolio Segment [Member]
Balance	5,063,000	4,485,000
Charge-offs	0	(42,000)
Recoveries	0	0
Provisions (credits)	(174,000)	(289,000)
Balance	4,889,000	4,154,000
Total loans receivable, gross	413,104,000		365,247,000
Commercial Real Estate Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	5,063,000
Balance	4,889,000
Allowance for loan losses: Individually evaluated for impairment	1,752,000		1,567,000
Allowance for loan losses: Collectively evaluated for impairment	3,137,000		3,496,000
Loans receivable, gross: Individually evaluated for impairment	15,643,000		15,704,000
Loans receivable, gross: Collectively evaluated for impairment	397,461,000		349,543,000
Total loans receivable, gross	413,104,000		365,247,000
Residential Portfolio Segment [Member]
Balance	1,700,000	1,379,000
Charge-offs	0	(3,000)
Recoveries	1,000	0
Provisions (credits)	(189,000)	533,000
Balance	1,512,000	1,909,000
Total loans receivable, gross	146,221,000		158,591,000
Residential Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	1,700,000
Balance	1,512,000
Allowance for loan losses: Individually evaluated for impairment	3,000		3,000
Allowance for loan losses: Collectively evaluated for impairment	1,509,000		1,697,000
Loans receivable, gross: Individually evaluated for impairment	2,940,000		2,954,000
Loans receivable, gross: Collectively evaluated for impairment	143,281,000		155,637,000
Total loans receivable, gross	146,221,000		158,591,000
Commercial Portfolio Segment [Member]
Balance	2,532,000	3,284,000
Charge-offs	(68,000)	(209,000)
Recoveries	15,000	12,000
Provisions (credits)	381,000	537,000
Balance	2,860,000	3,624,000
Total loans receivable, gross	128,515,000		122,810,000
Commercial Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	2,532,000
Balance	2,860,000
Allowance for loan losses: Individually evaluated for impairment	954,000		722,000
Allowance for loan losses: Collectively evaluated for impairment	1,906,000		1,810,000
Loans receivable, gross: Individually evaluated for impairment	4,544,000		4,031,000
Loans receivable, gross: Collectively evaluated for impairment	123,971,000		118,779,000
Total loans receivable, gross	128,515,000		122,810,000
Consumer Portfolio Segment [Member]
Balance	253,000	295,000
Charge-offs	(47,000)	(18,000)
Recoveries	1,000	102,000
Provisions (credits)	112,000	3,000
Balance	319,000	382,000
Total loans receivable, gross	71,219,000		59,364,000
Consumer Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	253,000
Balance	319,000
Allowance for loan losses: Individually evaluated for impairment	0		0
Allowance for loan losses: Collectively evaluated for impairment	319,000		253,000
Loans receivable, gross: Individually evaluated for impairment	521,000		523,000
Loans receivable, gross: Collectively evaluated for impairment	70,698,000		58,841,000
Total loans receivable, gross	71,219,000		59,364,000
Construction Portfolio Segment [Member]
Balance	78,000	739,000
Charge-offs	(70,000)	0
Recoveries	0	0
Provisions (credits)	48,000	(459,000)
Balance	56,000	280,000
Total loans receivable, gross	12,223,000		21,781,000
Construction Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	78,000
Balance	56,000
Allowance for loan losses: Individually evaluated for impairment	0		0
Allowance for loan losses: Collectively evaluated for impairment	56,000		78,000
Loans receivable, gross: Individually evaluated for impairment	0		0
Loans receivable, gross: Collectively evaluated for impairment	12,223,000		21,781,000
Total loans receivable, gross	12,223,000		21,781,000
Construction to Permanent Portfolio Segment [Member]
Balance	41,000	162,000
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	(32,000)	(85,000)
Balance	9,000	77,000
Total loans receivable, gross	2,057,000		11,695,000
Construction to Permanent Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance	41,000
Balance	9,000
Allowance for loan losses: Individually evaluated for impairment	0		0
Allowance for loan losses: Collectively evaluated for impairment	9,000		41,000
Loans receivable, gross: Individually evaluated for impairment	0		0
Loans receivable, gross: Collectively evaluated for impairment	2,057,000		11,695,000
Total loans receivable, gross	2,057,000		11,695,000
Unallocated Financing Receivables [Member]
Balance	238,000	240,000
Charge-offs	0	0
Recoveries	0	0
Provisions (credits)	(146,000)	(240,000)
Balance	92,000	$ 0
Unallocated Financing Receivables [Member] \| Business Activities Loans [Member]
Balance	238,000
Balance	92,000
Allowance for loan losses: Individually evaluated for impairment	0		0
Allowance for loan losses: Collectively evaluated for impairment	92,000		238,000
Loans receivable, gross: Individually evaluated for impairment	0		0
Loans receivable, gross: Collectively evaluated for impairment	0		0
Total loans receivable, gross	$ 0		$ 0

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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