Note 6 - Loans Receivable and Allowances for Loan Losses - Activity in Allowance for Loan Losses (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
Beginning balance	$ 6,650	$ 9,181	$ 8,599	$ 9,155
Charge-offs	(14)	(258)	(2,363)	(268)
Recoveries	130	31	130	67
Provision for loan losses	800	500	1,200	500
Ending balance	7,566	9,454	7,566	9,454
Allowance for loan losses, individually evaluated for impairment					$ 891	$ 2,790
Allowance for loan losses, collectively evaluated for impairment					6,675	5,809
Total allowance for loan losses	6,650	9,181	7,566	9,454	7,566	8,599
Loans evaluated individually					24,784	24,716
Loans evaluated collectively					1,292,655	1,137,333
Total loans receivable					1,317,439	1,162,049
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	1,903	2,962	3,774	3,254
Charge-offs			(1,535)
Recoveries	33		33	7
Provision for loan losses	103	209	(233)	(90)
Ending balance	2,039	3,171	2,039	3,171
Allowance for loan losses, individually evaluated for impairment						1,964
Allowance for loan losses, collectively evaluated for impairment					2,039	1,810
Total allowance for loan losses	1,903	2,962	2,039	3,171	2,039	3,774
Loans evaluated individually					13,811	15,415
Loans evaluated collectively					475,763	417,889
Total loans receivable					489,574	433,304
Construction and Land Development Portfolio Segment [Member]
Beginning balance	751	546	725	557
Charge-offs
Recoveries
Provision for loan losses	21	34	47	23
Ending balance	772	580	772	580
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment					772	725
Total allowance for loan losses	751	546	772	580	772	725
Loans evaluated individually
Loans evaluated collectively					120,165	104,617
Total loans receivable					120,165	104,617
Commercial Portfolio Segment [Member]
Beginning balance	1,261	2,770	1,317	2,884
Charge-offs		(152)	(151)	(152)
Recoveries	76	30	76	59
Provision for loan losses	112	(152)	207	(295)
Ending balance	1,449	2,496	1,449	2,496
Allowance for loan losses, individually evaluated for impairment					622	374
Allowance for loan losses, collectively evaluated for impairment					827	943
Total allowance for loan losses	1,261	2,770	1,449	2,496	1,449	1,317
Loans evaluated individually					6,783	4,501
Loans evaluated collectively					181,471	168,842
Total loans receivable					188,254	173,343
Owner Occupied Real Estate [Member]
Beginning balance	1,692	1,627	1,737	1,382
Charge-offs		(100)	(465)	(108)
Recoveries	20		20
Provision for loan losses	144	71	564	324
Ending balance	1,856	1,598	1,856	1,598
Allowance for loan losses, individually evaluated for impairment					201	235
Allowance for loan losses, collectively evaluated for impairment					1,655	1,502
Total allowance for loan losses	1,692	1,627	1,856	1,598	1,856	1,737
Loans evaluated individually					3,400	3,798
Loans evaluated collectively					332,471	306,040
Total loans receivable					335,871	309,838
Consumer Portfolio Segment [Member]
Beginning balance	460	575	573	588
Charge-offs	(14)	(6)	(212)	(8)
Recoveries	1	1	1	1
Provision for loan losses	62	(26)	147	(37)
Ending balance	509	544	509	544
Allowance for loan losses, individually evaluated for impairment					68	217
Allowance for loan losses, collectively evaluated for impairment					441	356
Total allowance for loan losses	460	575	509	544	509	573
Loans evaluated individually					790	1,002
Loans evaluated collectively					82,677	75,181
Total loans receivable					83,467	76,183
Residential Portfolio Segment [Member]
Beginning balance	508	130	392	58
Charge-offs
Recoveries
Provision for loan losses	130	108	246	180
Ending balance	638	238	638	238
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment					638	392
Total allowance for loan losses	508	130	638	238	638	392
Loans evaluated individually
Loans evaluated collectively					100,108	64,764
Total loans receivable					100,108	64,764
Unallocated Financing Receivables [Member]
Beginning balance	75	571	81	432
Charge-offs
Recoveries
Provision for loan losses	228	256	222	395
Ending balance	303	827	303	827
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment					303	81
Total allowance for loan losses	$ 75	$ 571	$ 303	$ 827	303	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 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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