Note 4 - Loans - Allowance for Credit Losses and Recorded Investment in Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Balance	$ 12,292	$ 11,925
Charge-offs	(348)	(390)
Recoveries	298	760
Provision for loan and lease losses
Balance	12,242	12,295
Individually evaluated for impairment			$ 1,366	$ 1,237
Collectively evaluated for impairment			10,876	11,055
Total	12,292	11,925	12,242	12,292
Individually evaluated for impairment			21,215	11,012
Collectively evaluated for impairment			1,013,391	935,239
Total gross loans			1,034,606	946,251
Commercial Portfolio Segment [Member]
Balance	2,205	2,397
Charge-offs
Recoveries	153	453
Provision for loan and lease losses	121	(552)
Balance	2,479	2,298
Individually evaluated for impairment			923	748
Collectively evaluated for impairment			1,556	1,457
Total	2,205	2,397	2,479	2,205
Individually evaluated for impairment			2,205	2,183
Collectively evaluated for impairment			147,370	133,360
Total gross loans			149,575	135,543
Commercial Real Estate Portfolio Segment [Member]
Balance	7,116	6,514
Charge-offs
Recoveries
Provision for loan and lease losses	(160)	384
Balance	6,956	6,898
Individually evaluated for impairment			169	209
Collectively evaluated for impairment			6,787	6,907
Total	7,116	6,514	6,956	7,116
Individually evaluated for impairment			11,671	1,343
Collectively evaluated for impairment			696,811	659,550
Total gross loans			708,482	660,893
Residential Portfolio Segment [Member]
Balance	1,173	1,169
Charge-offs	(68)	(114)
Recoveries	82	246
Provision for loan and lease losses	24	(152)
Balance	1,211	1,149
Individually evaluated for impairment			267	273
Collectively evaluated for impairment			944	900
Total	1,173	1,169	1,211	1,173
Individually evaluated for impairment			7,316	7,463
Collectively evaluated for impairment			123,083	91,307
Total gross loans			130,399	98,770
Consumer Portfolio Segment [Member]
Balance	1,356	1,435
Charge-offs	(280)	(276)
Recoveries	63	61
Provision for loan and lease losses	(83)	253
Balance	1,056	1,473
Individually evaluated for impairment			7	7
Collectively evaluated for impairment			1,049	1,349
Total	1,356	1,435	1,056	1,356
Individually evaluated for impairment			23	23
Collectively evaluated for impairment			46,127	51,022
Total gross loans			46,150	51,045
Unallocated Financing Receivables [Member]
Balance	442	410
Charge-offs
Recoveries
Provision for loan and lease losses	98	67
Balance	540	477
Individually evaluated for impairment
Collectively evaluated for impairment			540	442
Total	$ 442	$ 410	540	442
Individually evaluated for impairment
Collectively evaluated for impairment
Total gross loans

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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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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