Note 4 - Loans Receivable and Related Allowance for Loan Losses - Activity in Allowance for Loan Losses by Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Beginning Balance	$ 6,508	$ 6,127
Charge-offs	(129)	(585)
Recoveries	80	13
Provision	180	380
Ending Balance	6,639	5,935
Individually evaluated for impairment			$ 70	$ 12
Total	6,639	6,127	6,639	6,508
Individually evaluated for impairment			520	468
Loans, gross			706,991	715,172
Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			151,421	159,374
Financial Asset Originated [Member]
Loans collectively evaluated for impairment			6,569	6,496
Loans collectively evaluated for impairment			555,050	555,330
Residential Portfolio Segment [Member]
Beginning Balance	2,198	2,090
Charge-offs	(10)	(62)
Recoveries	40	3
Provision	28	(112)
Ending Balance	2,256	1,919
Individually evaluated for impairment			7	12
Total	2,198	2,090	2,256	2,198
Individually evaluated for impairment			380	389
Loans, gross			293,903	295,405
Residential Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			70,981	72,654
Residential Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			2,249	2,186
Loans collectively evaluated for impairment			222,542	222,362
Home Equity Loans and Lines of Credit [Member]
Beginning Balance	648	646
Charge-offs	(4)	(19)
Recoveries	1	1
Provision	5	23
Ending Balance	650	651
Individually evaluated for impairment
Total	648	646	650	648
Individually evaluated for impairment			5	6
Loans, gross			102,553	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			13,131	13,750
Home Equity Loans and Lines of Credit [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			650	648
Loans collectively evaluated for impairment			89,417	89,996
Commercial Real Estate Portfolio Segment [Member]
Beginning Balance	3,106	2,753
Charge-offs	(5)	(385)
Recoveries	15	2
Provision	(73)	381
Ending Balance	3,043	2,751
Individually evaluated for impairment
Total	3,106	2,753	3,043	3,106
Individually evaluated for impairment			32	34
Loans, gross			232,315	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			54,151	56,690
Commercial Real Estate Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			3,043	3,106
Loans collectively evaluated for impairment			178,132	182,010
Commercial Portfolio Segment [Member]
Beginning Balance	500	585
Charge-offs	(71)
Recoveries		1
Provision	206	(26)
Ending Balance	635	560
Individually evaluated for impairment			63
Total	500	585	635	500
Individually evaluated for impairment			103	39
Loans, gross			67,317	66,009
Commercial Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			10,258	12,974
Commercial Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			572	500
Loans collectively evaluated for impairment			56,956	52,996
Consumer Portfolio Segment [Member]
Beginning Balance	56	53
Charge-offs	(39)	(119)
Recoveries	24	6
Provision	14	114
Ending Balance	55	54
Individually evaluated for impairment
Total	$ 56	$ 53	55	56
Individually evaluated for impairment
Loans, gross			10,903	11,272
Consumer Portfolio Segment [Member] \| Financial Asset Acquired and No Credit Deterioration [Member]
Loans collectively evaluated for impairment
Loans collectively evaluated for impairment			2,900	3,306
Consumer Portfolio Segment [Member] \| Financial Asset Originated [Member]
Loans collectively evaluated for impairment			55	56
Loans collectively evaluated for impairment			$ 8,003	$ 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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- Definition

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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The balance of financing receivables 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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