Note 8 - Loans and Allowance for Loan Losses - Allowance for Loan Losses and the Recorded Investment In Loans by Impairment Method (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Individually evaluated for impairment	$ 3,173	$ 3,182
Collectively evaluated for impairment	6,575	6,601
Total ending allowance balance	9,748	9,783	$ 9,507	$ 9,344
Loans individually evaluated for impairment	22,477	23,141
Loans collectively evaluated for impairment	1,012,992	1,012,122
Loans, net of unearned income	1,035,469	1,035,263
Real Estate Portfolio Segment [Member]
Individually evaluated for impairment	2,747	2,694
Collectively evaluated for impairment	5,854	5,815
Total ending allowance balance	8,601	8,509	8,184	8,205
Loans individually evaluated for impairment	21,781	22,381
Loans collectively evaluated for impairment	902,113	894,425
Loans, net of unearned income	923,894	916,806
Commercial Portfolio Segment [Member]
Individually evaluated for impairment	214	270
Collectively evaluated for impairment	622	681
Total ending allowance balance	836	951	864	854
Loans individually evaluated for impairment	391	448
Loans collectively evaluated for impairment	103,627	110,094
Loans, net of unearned income	104,018	110,542
Consumer Portfolio Segment [Member]
Individually evaluated for impairment	212	218
Collectively evaluated for impairment	99	105
Total ending allowance balance	311	323	$ 459	$ 285
Loans individually evaluated for impairment	305	312
Loans collectively evaluated for impairment	7,252	7,603
Loans, net of unearned income	$ 7,557	$ 7,915

A valuation allowance for financing receivables that are expected to be uncollectible.

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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 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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