Note 4 - Loan Receivable and Allowance for Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Balance	$ 10,426	$ 10,916	$ 10,584	$ 10,115
Charge-offs	(80)	(691)	(352)	(735)
Recoveries	16	13	130	54
Provisions (credits)		910		1,714
Balance	10,362	11,148	10,362	11,148
Total allowance for loan and lease losses	10,362	11,148	10,362	11,148	$ 10,584
Total loans receivable, gross	670,896		670,896		730,180
Business Activities Loans [Member]
Balance			10,584
Balance	10,362		10,362
Allowance for loan losses: Individually evaluated for impairment	1,653		1,653		1,412
Allowance for loan losses: Collectively evaluated for impairment	8,709		8,709		9,172
Total allowance for loan and lease losses	10,362		10,362		10,584
Loans receivable, gross: Individually evaluated for impairment	28,097		28,097		24,383
Loans receivable, gross: Collectively evaluated for impairment	642,799		642,799		705,797
Total loans receivable, gross	670,896		670,896		730,180
Commercial Real Estate Portfolio Segment [Member]
Balance	4,154	4,150	4,485	3,789
Charge-offs	(9)		(51)
Provisions (credits)	(66)	124	(355)	485
Balance	4,079	4,274	4,079	4,274
Total allowance for loan and lease losses	4,079	4,274	4,079	4,274	4,485
Total loans receivable, gross	272,854		272,854		282,378
Commercial Real Estate Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance			4,485
Balance	4,079		4,079
Allowance for loan losses: Individually evaluated for impairment	1,252		1,252		1,398
Allowance for loan losses: Collectively evaluated for impairment	2,827		2,827		3,087
Total allowance for loan and lease losses	4,079		4,079		4,485
Loans receivable, gross: Individually evaluated for impairment	16,964		16,964		14,534
Loans receivable, gross: Collectively evaluated for impairment	255,890		255,890		267,844
Total loans receivable, gross	272,854		272,854		282,378
Residential Portfolio Segment [Member]
Balance	1,909	1,120	1,379	1,038
Charge-offs	0	(12)	(3)	(13)
Provisions (credits)	94	802	627	885
Balance	2,003	1,910	2,003	1,910
Total allowance for loan and lease losses	2,003	1,910	2,003	1,910	1,379
Total loans receivable, gross	158,088		158,088		153,851
Residential Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance			1,379
Balance	2,003		2,003
Allowance for loan losses: Individually evaluated for impairment	5		5		4
Allowance for loan losses: Collectively evaluated for impairment	1,998		1,998		1,375
Total allowance for loan and lease losses	2,003		2,003		1,379
Loans receivable, gross: Individually evaluated for impairment	4,200		4,200		3,962
Loans receivable, gross: Collectively evaluated for impairment	153,888		153,888		149,889
Total loans receivable, gross	158,088		158,088		153,851
Commercial Portfolio Segment [Member]
Balance	3,624	4,390	3,284	4,340
Charge-offs	0	(679)	(209)	(683)
Recoveries	12	11	24	51
Provisions (credits)	(424)	(196)	113	(182)
Balance	3,212	3,526	3,212	3,526
Total allowance for loan and lease losses	3,212	3,526	3,212	3,526	3,284
Total loans receivable, gross	123,113		123,113		144,297
Commercial Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance			3,284
Balance	3,212		3,212
Allowance for loan losses: Individually evaluated for impairment	396		396		0
Allowance for loan losses: Collectively evaluated for impairment	2,816		2,816		3,284
Total allowance for loan and lease losses	3,212		3,212		3,284
Loans receivable, gross: Individually evaluated for impairment	6,406		6,406		4,700
Loans receivable, gross: Collectively evaluated for impairment	116,707		116,707		139,597
Total loans receivable, gross	123,113		123,113		144,297
Consumer Portfolio Segment [Member]
Balance	382	534	295	341
Charge-offs	(2)	0	(20)	(39)
Recoveries	4	2	106	3
Provisions (credits)	7	(2)	10	229
Balance	391	534	391	534
Total allowance for loan and lease losses	391	534	391	534	295
Total loans receivable, gross	51,386		51,386		67,635
Consumer Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance			295
Balance	391		391
Allowance for loan losses: Individually evaluated for impairment	0		0		10
Allowance for loan losses: Collectively evaluated for impairment	391		391		285
Total allowance for loan and lease losses	391		391		295
Loans receivable, gross: Individually evaluated for impairment	527		527		1,187
Loans receivable, gross: Collectively evaluated for impairment	50,859		50,859		66,448
Total loans receivable, gross	51,386		51,386		67,635
Construction Portfolio Segment [Member]
Balance	280	603	739	477
Charge-offs	(69)		(69)
Provisions (credits)	158	63	(301)	189
Balance	369	666	369	666
Total allowance for loan and lease losses	369	666	369	666	739
Total loans receivable, gross	46,879		46,879		66,984
Construction Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance			739
Balance	369		369
Allowance for loan losses: Individually evaluated for impairment	0		0		0
Allowance for loan losses: Collectively evaluated for impairment	369		369		739
Total allowance for loan and lease losses	369		369		739
Loans receivable, gross: Individually evaluated for impairment	0		0		0
Loans receivable, gross: Collectively evaluated for impairment	46,879		46,879		66,984
Total loans receivable, gross	46,879		46,879		66,984
Construction to Permanent Portfolio Segment [Member]
Balance	77	119	162	130
Provisions (credits)	67	30	(18)	19
Balance	144	149	144	149
Total allowance for loan and lease losses	144	149	144	149	162
Total loans receivable, gross	18,576		18,576		15,035
Construction to Permanent Portfolio Segment [Member] \| Business Activities Loans [Member]
Balance			162
Balance	144		144
Allowance for loan losses: Individually evaluated for impairment	0		0		0
Allowance for loan losses: Collectively evaluated for impairment	144		144		162
Total allowance for loan and lease losses	144		144		162
Loans receivable, gross: Individually evaluated for impairment	0		0		0
Loans receivable, gross: Collectively evaluated for impairment	18,576		18,576		15,035
Total loans receivable, gross	18,576		18,576		15,035
Unallocated Financing Receivables [Member]
Balance	0		240
Provisions (credits)	164	89	(76)	89
Balance	164	89	164	89
Total allowance for loan and lease losses	164	$ 89	164	$ 89	240
Unallocated Financing Receivables [Member] \| Business Activities Loans [Member]
Balance			240
Balance	164		164
Allowance for loan losses: Individually evaluated for impairment	0		0		0
Allowance for loan losses: Collectively evaluated for impairment	164		164		240
Total allowance for loan and lease losses	164		164		240
Loans receivable, gross: Individually evaluated for impairment	0		0		0
Loans receivable, gross: Collectively evaluated for impairment	0		0		0
Total loans receivable, gross	$ 0		$ 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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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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