Note 4 - Loans - Allowance for Credit Losses and Recorded Investment in Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Dec. 31, 2018
Balance	$ 12,242	$ 12,295	$ 12,292	$ 11,925
Charge-offs	(659)	(382)	(1,007)	(771)
Recoveries	862	475	1,160	1,234
Provision for loan and lease losses
Balance	12,445	12,388	12,445	12,388
Individually evaluated for impairment					$ 727	$ 1,237
Collectively evaluated for impairment					11,718	11,055
Total	12,242	12,295	12,445	12,388	12,445	12,292
Individually evaluated for impairment					19,937	11,012
Collectively evaluated for impairment					1,016,787	935,239
Total gross loans					1,036,724	946,251
Commercial Portfolio Segment [Member]
Balance	2,479	2,298	2,205	2,397
Charge-offs	(145)	(133)	(145)	(133)
Recoveries	757	350	911	803
Provision for loan and lease losses	(987)	(73)	(867)	(625)
Balance	2,104	2,442	2,104	2,442
Individually evaluated for impairment					385	748
Collectively evaluated for impairment					1,719	1,457
Total	2,479	2,298	2,104	2,442	2,104	2,205
Individually evaluated for impairment					1,286	2,183
Collectively evaluated for impairment					151,017	133,360
Total gross loans					152,303	135,543
Commercial Real Estate Portfolio Segment [Member]
Balance	6,956	6,898	7,116	6,514
Charge-offs	(233)		(233)
Recoveries
Provision for loan and lease losses	875	193	715	577
Balance	7,598	7,091	7,598	7,091
Individually evaluated for impairment					169	209
Collectively evaluated for impairment					7,429	6,907
Total	6,956	6,898	7,598	7,091	7,598	7,116
Individually evaluated for impairment					11,481	1,343
Collectively evaluated for impairment					705,621	659,550
Total gross loans					717,102	660,893
Residential Portfolio Segment [Member]
Balance	1,211	1,149	1,173	1,169
Charge-offs	(71)	(49)	(139)	(163)
Recoveries	18	47	100	293
Provision for loan and lease losses	(88)	(36)	(64)	(188)
Balance	1,070	1,111	1,070	1,111
Individually evaluated for impairment					166	273
Collectively evaluated for impairment					904	900
Total	1,211	1,149	1,070	1,111	1,070	1,173
Individually evaluated for impairment					7,148	7,463
Collectively evaluated for impairment					118,762	91,307
Total gross loans					125,910	98,770
Consumer Portfolio Segment [Member]
Balance	1,056	1,473	1,356	1,435
Charge-offs	(210)	(200)	(490)	(475)
Recoveries	87	78	149	138
Provision for loan and lease losses	137	(34)	55	219
Balance	1,070	1,317	1,070	1,317
Individually evaluated for impairment					7	7
Collectively evaluated for impairment					1,063	1,349
Total	1,056	1,473	1,070	1,317	1,070	1,356
Individually evaluated for impairment					22	23
Collectively evaluated for impairment					41,387	51,022
Total gross loans					41,409	51,045
Unallocated Financing Receivables [Member]
Balance	540	477	442	410
Charge-offs
Recoveries
Provision for loan and lease losses	63	(50)	161	17
Balance	603	427	603	427
Individually evaluated for impairment
Collectively evaluated for impairment					603	442
Total	$ 540	$ 477	$ 603	$ 427	603	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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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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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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The balance of financing receivables that were collectively evaluated for impairment.

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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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