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, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Dec. 31, 2017
Balance	$ 12,295	$ 11,641	$ 11,925	$ 11,544
Charge-offs	(382)	(359)	(771)	(806)
Recoveries	475	106	1,234	450
Provision for loan and lease losses		300		500
Balance	12,388	11,688	12,388	11,688
Individually evaluated for impairment					$ 1,165	$ 1,169
Collectively evaluated for impairment					11,223	10,756
Total	12,295	11,641	12,388	11,688	12,388	11,925
Individually evaluated for impairment					11,415	13,147
Collectively evaluated for impairment					925,401	866,688
Total gross loans					936,816	879,835
Commercial Portfolio Segment [Member]
Balance	2,298	2,649	2,397	2,849
Charge-offs	(133)		(133)	(51)
Recoveries	350	36	803	235
Provision for loan and lease losses	(73)	165	(625)	(183)
Balance	2,442	2,850	2,442	2,850
Individually evaluated for impairment					753	690
Collectively evaluated for impairment					1,689	1,707
Total	2,298	2,649	2,442	2,850	2,442	2,397
Individually evaluated for impairment					2,778	3,154
Collectively evaluated for impairment					136,892	139,251
Total gross loans					139,670	142,405
Commercial Real Estate Portfolio Segment [Member]
Balance	6,898	5,963	6,514	5,578
Charge-offs
Recoveries				27
Provision for loan and lease losses	193	109	577	467
Balance	7,091	6,072	7,091	6,072
Individually evaluated for impairment					119	77
Collectively evaluated for impairment					6,972	6,437
Total	6,898	5,963	7,091	6,072	7,091	6,514
Individually evaluated for impairment					799	1,403
Collectively evaluated for impairment					646,993	584,190
Total gross loans					647,792	585,593
Residential Portfolio Segment [Member]
Balance	1,149	1,490	1,169	1,716
Charge-offs	(49)	(115)	(163)	(284)
Recoveries	47	19	293	94
Provision for loan and lease losses	(36)	(197)	(188)	(329)
Balance	1,111	1,197	1,111	1,197
Individually evaluated for impairment					283	391
Collectively evaluated for impairment					828	778
Total	1,149	1,490	1,111	1,197	1,111	1,169
Individually evaluated for impairment					7,805	8,554
Collectively evaluated for impairment					93,889	93,358
Total gross loans					101,694	101,912
Consumer Portfolio Segment [Member]
Balance	1,473	1,074	1,435	955
Charge-offs	(200)	(244)	(475)	(471)
Recoveries	78	51	138	94
Provision for loan and lease losses	(34)	256	219	559
Balance	1,317	1,137	1,317	1,137
Individually evaluated for impairment					10	11
Collectively evaluated for impairment					1,307	1,424
Total	1,473	1,074	1,317	1,137	1,317	1,435
Individually evaluated for impairment					33	36
Collectively evaluated for impairment					47,627	49,889
Total gross loans					47,660	49,925
Unallocated Financing Receivables [Member]
Balance	477	465	410	446
Charge-offs
Recoveries
Provision for loan and lease losses	(50)	(33)	17	(14)
Balance	427	432	427	432
Individually evaluated for impairment
Collectively evaluated for impairment					427	410
Total	$ 477	$ 465	$ 427	$ 432	427	410
Individually evaluated for impairment
Collectively evaluated for impairment
Total gross loans

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

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

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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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