Note 3 - Loans Receivable - Allowance for Loan Losses Activity (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Allowance for loan losses, beginning balance	$ 6,130	$ 5,075	$ 5,750	$ 4,770
Charge-offs	(24)	(189)	(154)	(198)
Recoveries	20	37	28	50
Loan loss provision	24	302	526	603
Allowance for loan losses, ending balance	6,150	5,225	6,150	5,225
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment		38		38
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	6,150	5,187	6,150	5,187
Loans receivable	582,757	509,140	582,757	509,140	$ 514,247
Loans receivable, ending balance, loans individually evaluated for impairment	1,500	1,611	1,500	1,611
Loans receivable, ending balance, loans collectively evaluated for impairment	581,257	507,529	581,257	507,529
Residential Portfolio Segment [Member]
Allowance for loan losses, beginning balance	1,301	1,251	1,301	1,241
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Loan loss provision	0	0	0	10
Allowance for loan losses, ending balance	1,301	1,251	1,301	1,251
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	0	0	0	0
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	1,301	1,251	1,301	1,251
Loans receivable	143,323	140,346	143,323	140,346	135,217
Loans receivable, ending balance, loans individually evaluated for impairment	573	500	573	500
Loans receivable, ending balance, loans collectively evaluated for impairment	142,750	139,846	142,750	139,846
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, beginning balance	3,202	2,278	2,778	2,079
Charge-offs	0	0	0	0
Recoveries	4	0	7	0
Loan loss provision	24	100	445	299
Allowance for loan losses, ending balance	3,230	2,378	3,230	2,378
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	0	0	0	0
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	3,230	2,378	3,230	2,378
Loans receivable	281,525	246,005	281,525	246,005	244,783
Loans receivable, ending balance, loans individually evaluated for impairment	527	451	527	451
Loans receivable, ending balance, loans collectively evaluated for impairment	280,998	245,554	280,998	245,554
Home Equity Portfolio Segment [Member]
Allowance for loan losses, beginning balance	427	471	506	460
Charge-offs	0	0	(80)	0
Recoveries	0	34	1	39
Loan loss provision	0	0	0	6
Allowance for loan losses, ending balance	427	505	427	505
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	0	0	0	0
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	427	505	427	505
Loans receivable	53,178	49,266	53,178	49,266	52,672
Loans receivable, ending balance, loans individually evaluated for impairment	207	305	207	305
Loans receivable, ending balance, loans collectively evaluated for impairment	52,971	48,961	52,971	48,961
Consumer Portfolio Segment [Member]
Allowance for loan losses, beginning balance	200	210	225	193
Charge-offs	(23)	(90)	(50)	(99)
Recoveries	8	3	10	11
Loan loss provision	0	102	0	120
Allowance for loan losses, ending balance	185	225	185	225
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment		38		38
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	185	187	185	187
Loans receivable	16,635	15,293	16,635	15,293	15,712
Loans receivable, ending balance, loans individually evaluated for impairment	101	144	101	144
Loans receivable, ending balance, loans collectively evaluated for impairment	16,534	15,149	16,534	15,149
Commercial Portfolio Segment [Member]
Allowance for loan losses, beginning balance	1,000	865	940	797
Charge-offs	(1)	(99)	(24)	(99)
Recoveries	8	0	10	0
Loan loss provision	0	100	81	168
Allowance for loan losses, ending balance	1,007	866	1,007	866
Allowance for loan losses, ending balance, allocated to loans individually evaluated for impairment	0	0	0	0
Allowance for loan losses, ending balance, allocated to loans collectively evaluated for impairment	1,007	866	1,007	866
Loans receivable	88,096	58,230	88,096	58,230	$ 65,863
Loans receivable, ending balance, loans individually evaluated for impairment	92	211	92	211
Loans receivable, ending balance, loans collectively evaluated for impairment	$ 88,004	$ 58,019	$ 88,004	$ 58,019

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 loss from loan transactions.

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