LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Average Recorded Investment in Impaired Loans and Related Interest Income (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	$ 8,249	$ 7,130	$ 15,118
Interest Income Recognized	63	66	33
Commercial Real Estate \| Owner-occupied
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	1,495	1,000	1,758
Interest Income Recognized	2	6	0
Commercial Real Estate \| Non-owner occupied
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	1,842	392	6,831
Interest Income Recognized	0	0	0
Commercial Real Estate \| Multi-family
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	148	182	216
Interest Income Recognized	0	0	0
Commercial Real Estate \| Non-owner occupied residential
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	346	418	645
Interest Income Recognized	0	0	0
Acquisition and development \| 1-4 family residential construction
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	181	154	0
Interest Income Recognized	0	0	0
Acquisition and development \| Commercial and land development
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	1	0	3
Interest Income Recognized	0	0	0
Commercial and industrial
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	322	413	575
Interest Income Recognized	0	0	0
Residential mortgage \| First lien
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	3,234	4,012	4,525
Interest Income Recognized	59	58	33
Residential mortgage \| Home equity – term
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	19	61	98
Interest Income Recognized	0	0	0
Residential mortgage \| Home equity lines of credit
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	657	488	455
Interest Income Recognized	2	2	0
Installment and other loans
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	4	10	12
Interest Income Recognized	$ 0	$ 0	$ 0

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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