LOANS - Allowance for Loan Losses and Recorded Investment in Loans by Portfolio Segment and Based on Impairment Method (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	$ 6,760	$ 20,771
Collectively evaluated for impairment	31,643	24,665
Total ending allowance balance	38,403	45,436
Individually evaluated for impairment	27,434	27,035
Collectively evaluated for impairment	2,832,340	2,789,429
Total ending loans balance	2,859,774	2,816,464
Construction and land development
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	6,417	4,847
Total ending allowance balance	6,417	4,847
Individually evaluated for impairment	0	30
Collectively evaluated for impairment	627,178	591,511
Total ending loans balance	627,178	591,541
Commercial real estate:
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	9,018	8,113
Total ending allowance balance	9,018	8,113
Individually evaluated for impairment	3,460	0
Collectively evaluated for impairment	994,498	993,912
Total ending loans balance	997,958	993,912
Residential real estate:
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	0	17
Collectively evaluated for impairment	4,767	4,445
Total ending allowance balance	4,767	4,462
Individually evaluated for impairment	3,255	2,477
Collectively evaluated for impairment	645,331	641,124
Total ending loans balance	648,586	643,601
Commercial and industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	6,760	20,754
Collectively evaluated for impairment	11,386	7,203
Total ending allowance balance	18,146	27,957
Individually evaluated for impairment	20,719	24,528
Collectively evaluated for impairment	560,879	558,113
Total ending loans balance	581,598	582,641
Consumer and other
Financing Receivable, Allowance for Credit Losses [Line Items]
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	55	57
Total ending allowance balance	55	57
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	4,454	4,769
Total ending loans balance	$ 4,454	$ 4,769

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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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

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- Definition

Amount, before allowance for credit loss and fee, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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-Publisher FASB
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- Definition

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

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

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