Note 5 - Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Dec. 31, 2017
Balance	$ 1,809	$ 1,478	$ 1,800	$ 1,478
Provision for loan losses	189	52	304	103
Loans charged off	(90)	(11)	(196)	(97)
Recoveries of loans previously charged off				35
Balance	1,908	1,519	1,908	1,519
Individually evaluated for impairment					$ 34	$ 179
Collectively evaluated for impairment					1,874	1,621
Total allowance for loan losses	1,908	1,478	1,908	1,519	1,908	1,800
Individually evaluated for impairment					1,572	2,304
Collectively evaluated for impairment					200,157	176,927
Total loans					201,729	179,231
Commercial Portfolio Segment [Member]
Balance	738	468	660	348
Provision for loan losses	92	37	170	157
Loans charged off	(24)		(24)
Recoveries of loans previously charged off
Balance	806	505	806	505
Individually evaluated for impairment
Collectively evaluated for impairment					806	660
Total allowance for loan losses	738	468	806	505	806	660
Individually evaluated for impairment					73	192
Collectively evaluated for impairment					78,171	64,643
Total loans					78,244	64,835
Residential Real Estate and Consumer [Member]
Balance	1,071	1,010	1,140	1,130
Provision for loan losses	97	15	134	(54)
Loans charged off	(66)	(11)	(172)	(97)
Recoveries of loans previously charged off				35
Balance	1,102	1,014	1,102	1,014
Individually evaluated for impairment					34	179
Collectively evaluated for impairment					1,068	961
Total allowance for loan losses	$ 1,071	$ 1,010	$ 1,102	$ 1,014	1,102	1,140
Individually evaluated for impairment					1,499	2,112
Collectively evaluated for impairment					121,986	112,284
Total loans					$ 123,485	$ 114,396

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 estimated loss from loan and lease transactions.

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