LOANS AND THE ALLOWANCE FOR LOAN LOSSES - Allowance for loan losses by portfolio (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 7,100	$ 6,702	$ 7,287	$ 6,478
Provision for credit losses		262	(187)	486
Recoveries		18		18
Ending balance	7,100	6,982	7,100	6,982
Individually evaluated	1,040		1,040		$ 6,565
Collectively evaluated	6,060		6,060		722
Loans individually evaluated	1,835		1,835		1,835
Loans collectively evaluated	839,654		839,654		810,862
Total Recorded Investment	841,489		841,489		812,697
Cash, Securities and Other
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	969	838	1,066	846
Provision for credit losses	(35)	287	(132)	279
Recoveries		2		2
Ending balance	934	1,127	934	1,127
Individually evaluated					1,066
Collectively evaluated	934		934
Loans collectively evaluated	135,393		135,393		131,756
Total Recorded Investment	135,393		135,393		131,756
Construction and Development
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	228	287	202	301
Provision for credit losses	(1)	(25)	25	(39)
Ending balance	227	262	227	262
Individually evaluated					202
Collectively evaluated	227		227
Loans collectively evaluated	35,760		35,760		24,914
Total Recorded Investment	35,760		35,760		24,914
1-4 Family Residential
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	2,334	1,849	2,283	1,833
Provision for credit losses	(377)	405	(326)	421
Recoveries		16		16
Ending balance	1,957	2,270	1,957	2,270
Individually evaluated					2,283
Collectively evaluated	1,957		1,957
Loans collectively evaluated	307,794		307,794		282,014
Total Recorded Investment	307,794		307,794		282,014
Non-Owner Occupied CRE
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	1,313	1,211	1,433	1,153
Provision for credit losses	(114)	251	(234)	309
Ending balance	1,199	1,462	1,199	1,462
Individually evaluated					1,433
Collectively evaluated	1,199		1,199
Loans collectively evaluated	164,438		164,438		176,987
Total Recorded Investment	164,438		164,438		176,987
Owner Occupied CRE
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	724	485	751	476
Provision for credit losses	(98)	224	(125)	233
Ending balance	626	709	626	709
Individually evaluated					751
Collectively evaluated	626		626
Loans collectively evaluated	98,393		98,393		92,742
Total Recorded Investment	98,393		98,393		92,742
Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Roll Forward]
Beginning balance	1,532	2,032	1,552	1,869
Provision for credit losses	625	(880)	605	(717)
Ending balance	2,157	$ 1,152	2,157	$ 1,152
Individually evaluated	1,040		1,040		830
Collectively evaluated	1,117		1,117		722
Loans individually evaluated	1,835		1,835		1,835
Loans collectively evaluated	97,876		97,876		102,449
Total Recorded Investment	$ 99,711		$ 99,711		$ 104,284

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

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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- Definition

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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