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, 2020	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	$ 10,872	$ 6,932	$ 8,249
Interest Income Recognized	50	54	63
Commercial Real Estate \| Owner-occupied
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	4,636	2,455	1,495
Interest Income Recognized	1	2	2
Commercial Real Estate \| Non-owner occupied
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	83	46	1,842
Interest Income Recognized	0	0	0
Commercial Real Estate \| Multi-family
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	205	152	148
Interest Income Recognized	0	0	0
Commercial Real Estate \| Non-owner occupied residential
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	388	217	346
Interest Income Recognized	0	0	0
Acquisition and development \| 1-4 family residential construction
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	0	0	181
Interest Income Recognized	0	0	0
Acquisition and development \| Commercial and land development
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	641	21	1
Interest Income Recognized	0	0	0
Commercial and industrial
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	1,196	683	322
Interest Income Recognized	0	0	0
Residential mortgage \| First lien
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	2,995	2,582	3,234
Interest Income Recognized	48	50	59
Residential mortgage \| Home-equity - term
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	11	13	19
Interest Income Recognized	0	0	0
Residential mortgage \| Home equity - lines of credit
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	692	750	657
Interest Income Recognized	1	2	2
Installment and other loans
Financing Receivable, Impaired [Line Items]
Average Impaired Balance	25	13	4
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=121611835&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=121611835&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.

+ References

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