Note 3 - Loans Receivable and Related Allowance for Loan Losses - Analysis of Changes in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Balance at the beginning of the year	$ 6,556	$ 6,508
Provision for loan losses	3,247	715
Charge-offs	(473)	(913)
Recoveries	250	246
Balance at the end of the year	9,580	6,556
Individually evaluated for impairment			$ 60	$ 5
Total	6,556	6,508	9,580	6,556
Individually evaluated for impairment			2,114	483
Loans and Leases Receivable, Net of Deferred Income, Total			809,918	701,904
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			89,761	123,329
Financial Asset Originated [Member]
Loans collectively evaluated for impairment			9,520	6,551
Loans collectively evaluated for impairment			718,043	578,092
Residential Portfolio Segment [Member]
Balance at the beginning of the year	2,309	2,198
Provision for loan losses	486	298
Charge-offs	(27)	(227)
Recoveries	6	40
Balance at the end of the year	2,774	2,309
Individually evaluated for impairment				5
Total	2,774	2,198	2,774	2,309
Individually evaluated for impairment			329	358
Loans and Leases Receivable, Net of Deferred Income, Total			308,031	293,170
Residential Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			44,209	60,523
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			2,774	2,304
Loans collectively evaluated for impairment			263,493	232,289
Home Equity Loans and Lines of Credit [Member]
Balance at the beginning of the year	626	648
Provision for loan losses	105	33
Charge-offs	(126)	(61)
Recoveries	15	6
Balance at the end of the year	620	626
Individually evaluated for impairment
Total	620	648	620	626
Individually evaluated for impairment			3	4
Loans and Leases Receivable, Net of Deferred Income, Total			87,088	97,541
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			8,491	10,901
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			620	626
Loans collectively evaluated for impairment			78,594	86,636
Commercial Real Estate Portfolio Segment [Member]
Balance at the beginning of the year	2,898	3,106
Provision for loan losses	2,250	(100)
Charge-offs	(75)	(242)
Recoveries	107	134
Balance at the end of the year	5,180	2,898
Individually evaluated for impairment			40
Total	5,180	3,106	5,180	2,898
Individually evaluated for impairment			1,639	81
Loans and Leases Receivable, Net of Deferred Income, Total			285,625	229,951
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			30,913	41,993
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			5,140	2,898
Loans collectively evaluated for impairment			253,073	187,877
Commercial Portfolio Segment [Member]
Balance at the beginning of the year	636	500
Provision for loan losses	134	386
Charge-offs	(163)	(250)
Recoveries	70
Balance at the end of the year	677	636
Individually evaluated for impairment			20
Total	677	500	677	636
Individually evaluated for impairment			143	40
Loans and Leases Receivable, Net of Deferred Income, Total			89,139	66,603
Commercial Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			5,131	7,930
Commercial Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			657	636
Loans collectively evaluated for impairment			83,865	58,633
Consumer Portfolio Segment [Member]
Balance at the beginning of the year	87	56
Provision for loan losses	272	98
Charge-offs	(82)	(133)
Recoveries	52	66
Balance at the end of the year	329	87
Individually evaluated for impairment
Total	$ 329	$ 56	329	87
Individually evaluated for impairment
Loans and Leases Receivable, Net of Deferred Income, Total			40,035	14,639
Consumer Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			1,017	1,982
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			329	87
Loans collectively evaluated for impairment			$ 39,018	$ 12,657

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 valuation allowance for financing receivables that are expected to be uncollectible that were individually 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 and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. 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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