Note 6 - Loans Receivable and Allowance for Loan Losses - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Beginning balance	$ 8,615	$ 8,599
Charge-offs	(1,017)	(2,349)
Recoveries	2
Provision for loan losses	300	400
Ending balance	7,900	6,650
Allowance for loan losses, individually evaluated for impairment			$ 517	$ 1,473
Allowance for loan losses, collectively evaluated for impairment			7,383	7,142
Total allowance for loan losses	8,615	8,599	7,900	8,615
Loans evaluated individually				18,030
Loans evaluated collectively			1,460,661	1,418,584
Total loans receivable			1,477,237	1,436,614
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	2,462	3,774
Charge-offs		(1,535)
Recoveries
Provision for loan losses	210	(336)
Ending balance	2,672	1,903
Allowance for loan losses, individually evaluated for impairment			244	295
Allowance for loan losses, collectively evaluated for impairment			2,428	2,167
Total allowance for loan losses	2,462	3,774	2,672	2,462
Loans evaluated individually			10,910	10,947
Loans evaluated collectively			516,094	504,791
Total loans receivable			527,004	515,738
Construction and Land Development Portfolio Segment [Member]
Beginning balance	777	725
Charge-offs
Recoveries
Provision for loan losses	(74)	26
Ending balance	703	751
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment			703	777
Total allowance for loan losses	777	725	703	777
Loans evaluated individually
Loans evaluated collectively			124,124	121,042
Total loans receivable			124,124	121,042
Commercial Portfolio Segment [Member]
Beginning balance	1,754	1,317
Charge-offs	(929)	(151)
Recoveries	1
Provision for loan losses	211	95
Ending balance	1,037	1,261
Allowance for loan losses, individually evaluated for impairment			209	867
Allowance for loan losses, collectively evaluated for impairment			828	887
Total allowance for loan losses	1,754	1,317	1,037	1,754
Loans evaluated individually			2,556	3,662
Loans evaluated collectively			202,081	196,761
Total loans receivable			204,637	200,423
Owner Occupied Real Estate [Member]
Beginning balance	2,033	1,737
Charge-offs	(75)	(465)
Recoveries
Provision for loan losses	(91)	420
Ending balance	1,867	1,692
Allowance for loan losses, individually evaluated for impairment			64	217
Allowance for loan losses, collectively evaluated for impairment			1,803	1,816
Total allowance for loan losses	2,033	1,737	1,867	2,033
Loans evaluated individually			2,290	2,560
Loans evaluated collectively			374,555	365,335
Total loans receivable			376,845	367,895
Consumer Portfolio Segment [Member]
Beginning balance	577	573
Charge-offs	(13)	(198)
Recoveries	1
Provision for loan losses	(29)	85
Ending balance	536	460
Allowance for loan losses, individually evaluated for impairment				94
Allowance for loan losses, collectively evaluated for impairment			536	483
Total allowance for loan losses	577	573	536	577
Loans evaluated individually				861
Loans evaluated collectively			92,059	90,291
Total loans receivable			92,879	91,152
Residential Portfolio Segment [Member]
Beginning balance	894	392
Charge-offs
Recoveries
Provision for loan losses	91	116
Ending balance	985	508
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment			985	894
Total allowance for loan losses	894	392	985	894
Loans evaluated individually
Loans evaluated collectively			151,748	140,364
Total loans receivable			151,748	140,364
Unallocated Financing Receivables [Member]
Beginning balance	118	81
Charge-offs
Recoveries
Provision for loan losses	(18)	(6)
Ending balance	100	75
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment			100	118
Total allowance for loan losses	$ 118	$ 81	100	118
Loans evaluated individually
Loans evaluated collectively
Total loans receivable

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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