Note 6 - Loans Receivable and Allowances for Loan Losses - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Dec. 31, 2017
Beginning balance	$ 7,566	$ 9,454	$ 8,599	$ 9,155
Charge-offs	(1)	(1,248)	(2,364)	(1,516)
Recoveries	19	52	149	119
Provision for loan losses	500		1,700	500
Ending balance	8,084	8,258	8,084	8,258
Allowance for loan losses, individually evaluated for impairment					$ 1,313	$ 2,790
Allowance for loan losses, collectively evaluated for impairment					6,771	5,809
Total allowance for loan losses	7,566	9,454	8,084	8,258	8,084	8,599
Loans evaluated individually					21,325	24,716
Loans evaluated collectively					1,357,438	1,137,333
Total loans receivable					1,378,763	1,162,049
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	2,039	3,171	3,774	3,254
Charge-offs			(1,535)
Recoveries	17	47	50	54
Provision for loan losses	202	381	(31)	291
Ending balance	2,258	3,599	2,258	3,599
Allowance for loan losses, individually evaluated for impairment					194	1,964
Allowance for loan losses, collectively evaluated for impairment					2,064	1,810
Total allowance for loan losses	2,039	3,171	2,258	3,599	2,258	3,774
Loans evaluated individually					13,510	15,415
Loans evaluated collectively					482,019	417,889
Total loans receivable					495,529	433,304
Construction and Land Development Portfolio Segment [Member]
Beginning balance	772	580	725	557
Charge-offs
Recoveries
Provision for loan losses	34	69	81	92
Ending balance	806	649	806	649
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment					806	725
Total allowance for loan losses	772	580	806	649	806	725
Loans evaluated individually
Loans evaluated collectively					125,512	104,617
Total loans receivable					125,512	104,617
Commercial Portfolio Segment [Member]
Beginning balance	1,449	2,496	1,317	2,884
Charge-offs		(1,195)	(151)	(1,347)
Recoveries	1	5	77	64
Provision for loan losses	193	(85)	400	(380)
Ending balance	1,643	1,221	1,643	1,221
Allowance for loan losses, individually evaluated for impairment					792	374
Allowance for loan losses, collectively evaluated for impairment					851	943
Total allowance for loan losses	1,449	2,496	1,643	1,221	1,643	1,317
Loans evaluated individually					3,979	4,501
Loans evaluated collectively					191,514	168,842
Total loans receivable					195,493	173,343
Owner Occupied Real Estate [Member]
Beginning balance	1,856	1,598	1,737	1,382
Charge-offs		(49)	(465)	(157)
Recoveries			20
Provision for loan losses	156	87	720	411
Ending balance	2,012	1,636	2,012	1,636
Allowance for loan losses, individually evaluated for impairment					242	235
Allowance for loan losses, collectively evaluated for impairment					1,770	1,502
Total allowance for loan losses	1,856	1,598	2,012	1,636	2,012	1,737
Loans evaluated individually					3,035	3,798
Loans evaluated collectively					355,921	306,040
Total loans receivable					358,956	309,838
Consumer Portfolio Segment [Member]
Beginning balance	509	544	573	588
Charge-offs	(1)	(4)	(213)	(12)
Recoveries	1		2	1
Provision for loan losses	38	11	185	(26)
Ending balance	547	551	547	551
Allowance for loan losses, individually evaluated for impairment					85	217
Allowance for loan losses, collectively evaluated for impairment					462	356
Total allowance for loan losses	509	544	547	551	547	573
Loans evaluated individually					801	1,002
Loans evaluated collectively					86,096	75,181
Total loans receivable					86,897	76,183
Residential Portfolio Segment [Member]
Beginning balance	638	238	392	58
Charge-offs
Recoveries
Provision for loan losses	103	85	349	265
Ending balance	741	323	741	323
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment					741	392
Total allowance for loan losses	638	238	741	323	741	392
Loans evaluated individually
Loans evaluated collectively					116,376	64,764
Total loans receivable					116,376	64,764
Unallocated Financing Receivables [Member]
Beginning balance	303	827	81	432
Charge-offs
Recoveries
Provision for loan losses	(226)	(548)	(4)	(153)
Ending balance	77	279	77	279
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment					77	81
Total allowance for loan losses	$ 303	$ 827	$ 77	$ 279	77	81
Loans evaluated individually
Loans evaluated collectively
Total loans receivable

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

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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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