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, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Balance at the beginning of the year	$ 6,508	$ 6,127
Provision for loan losses	715	1,280
Charge-offs	(913)	(989)
Recoveries	246	90
Balance at the end of the year	6,556	6,508
Individually evaluated for impairment			$ 5	$ 12
Total	6,508	6,127	6,556	6,508
Individually evaluated for impairment			483	468
Total			701,904	715,172
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			123,329	159,374
Financial Asset Originated [Member]
Loans collectively evaluated for impairment			6,551	6,496
Loans collectively evaluated for impairment			578,092	555,330
Residential Portfolio Segment [Member]
Balance at the beginning of the year	2,198	2,090
Provision for loan losses	298	176
Charge-offs	(227)	(71)
Recoveries	40	3
Balance at the end of the year	2,309	2,198
Individually evaluated for impairment			5	12
Total	2,309	2,090	2,309	2,198
Individually evaluated for impairment			358	389
Total			293,170	295,405
Residential Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			60,523	72,654
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			2,304	2,186
Loans collectively evaluated for impairment			232,289	222,362
Home Equity Loans and Lines of Credit [Member]
Balance at the beginning of the year	648	646
Provision for loan losses	33	143
Charge-offs	(61)	(155)
Recoveries	6	14
Balance at the end of the year	626	648
Individually evaluated for impairment
Total	626	646	626	648
Individually evaluated for impairment			4	6
Total			97,541	103,752
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			10,901	13,750
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			626	648
Loans collectively evaluated for impairment			86,636	89,996
Commercial Real Estate Portfolio Segment [Member]
Balance at the beginning of the year	3,106	2,753
Provision for loan losses	(100)	789
Charge-offs	(242)	(484)
Recoveries	134	48
Balance at the end of the year	2,898	3,106
Individually evaluated for impairment
Total	2,898	2,753	2,898	3,106
Individually evaluated for impairment			81	34
Total			229,951	238,734
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			41,993	56,690
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			2,898	3,106
Loans collectively evaluated for impairment			187,877	182,010
Commercial Portfolio Segment [Member]
Balance at the beginning of the year	500	585
Provision for loan losses	386	(86)
Charge-offs	(250)
Recoveries		1
Balance at the end of the year	636	500
Individually evaluated for impairment
Total	636	585	636	500
Individually evaluated for impairment			40	39
Total			66,603	66,009
Commercial Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			7,930	12,974
Commercial Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			636	500
Loans collectively evaluated for impairment			58,633	52,996
Consumer Portfolio Segment [Member]
Balance at the beginning of the year	56	53
Provision for loan losses	98	258
Charge-offs	(133)	(279)
Recoveries	66	24
Balance at the end of the year	87	56
Individually evaluated for impairment
Total	$ 87	$ 53	87	56
Individually evaluated for impairment
Total			14,639	11,272
Consumer Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			1,982	3,306
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			87	56
Loans collectively evaluated for impairment			$ 12,657	$ 7,966

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 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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