Allegiance Bancshares (ABTX) 10-Q 29 Apr 21 2021 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2021	Apr. 27, 2021
Cover [Abstract]
Entity Registrant Name	Allegiance Bancshares, Inc.
Entity Central Index Key	0001642081
Trading Symbol	ABTX
Security Exchange Name	NASDAQ
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Title of 12(b) Security	Common Stock, par value, $1.00 per share
Document Type	10-Q
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity File Number	001-37585
Entity Incorporation, State or Country Code	TX
Entity Tax Identification Number	26-3564100
Entity Address, Address Line One	8847 West Sam Houston Parkway, N.
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77040
City Area Code	281
Local Phone Number	894-3200
Entity Common Stock, Shares Outstanding (in shares)		20,183,015
Document Quarterly Report	true
Document Transition Report	false

CONSOLIDATED BALANCE SHEETS (Un

CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
ASSETS
Cash and due from banks	$ 141,947	$ 122,897
Interest-bearing deposits at other financial institutions	482,383	299,869
Total cash and cash equivalents	624,330	422,766
Available for sale securities, at fair value	787,516	772,890
Loans held for investment	4,659,169	4,491,764
Less: allowance for credit losses on loans	(52,758)	(53,173)
Loans, net	4,606,411	4,438,591
Accrued interest receivable	38,632	40,053
Premises and equipment, net	66,115	70,685
Other real estate owned	576	9,196
Federal Home Loan Bank stock	7,775	7,756
Bank owned life insurance	27,825	27,686
Goodwill	223,642	223,642
Core deposit intangibles, net	17,130	17,954
Other assets	31,038	18,909
TOTAL ASSETS	6,430,990	6,050,128
Deposits:
Noninterest-bearing	1,914,121	1,704,567
Interest-bearing
Demand	480,710	437,328
Money market and savings	1,617,823	1,499,938
Certificates and other time	1,361,535	1,346,649
Total interest-bearing deposits	3,460,068	3,283,915
Total deposits	5,374,189	4,988,482
Accrued interest payable	3,862	2,701
Borrowed funds	147,517	155,515
Subordinated debt	108,453	108,322
Other liabilities	36,432	36,439
Total liabilities	5,670,453	5,291,459
COMMITMENTS AND CONTINGENCIES (See Note 14)
SHAREHOLDERS’ EQUITY:
Preferred stock, $1 par value; 1,000,000 shares authorized; no shares issued or outstanding
Common stock, $1 par value; 80,000,000 shares authorized; 20,182,971 shares issued and outstanding at March 31, 2021 and 20,208,323 shares issued and outstanding at December 31, 2020	20,183	20,208
Capital surplus	505,307	508,794
Retained earnings	210,834	195,236
Accumulated other comprehensive income	24,213	34,431
Total shareholders’ equity	760,537	758,669
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	$ 6,430,990	$ 6,050,128

CONSOLIDATED BALANCE SHEETS (_2

CONSOLIDATED BALANCE SHEETS (Unaudited) (Parentheticals) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	1,000,000	1,000,000
Shares issued (in shares)	0	0
Shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	80,000,000	80,000,000
Common stock, shares issued (in shares)	20,182,971	20,208,323
Common stock, shares outstanding (in shares)	20,182,971	20,208,323

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
INTEREST INCOME:
Loans, including fees	$ 57,991	$ 54,624
Securities:
Taxable	2,402	2,087
Tax-exempt	2,394	546
Deposits in other financial institutions	41	195
Total interest income	62,828	57,452
INTEREST EXPENSE:
Demand, money market and savings deposits	1,484	4,364
Certificates and other time deposits	3,665	6,084
Borrowed funds	539	506
Subordinated debt	1,442	1,473
Total interest expense	7,130	12,427
NET INTEREST INCOME	55,698	45,025
Provision for credit losses	639	10,990
Net interest income after provision for credit losses	55,059	34,035
NONINTEREST INCOME:
Gain on sale of securities	49	194
Loss on sale of other real estate and other repossessed assets	(176)	(69)
Bank owned life insurance income	139	151
Rebate from correspondent bank	132	493
Other	1,121	1,330
Total noninterest income	1,736	2,725
NONINTEREST EXPENSE:
Salaries and employee benefits	22,452	19,781
Net occupancy and equipment	2,390	1,907
Depreciation	1,034	866
Data processing and software amortization	2,200	1,826
Professional fees	789	573
Regulatory assessments and FDIC insurance	807	632
Core deposit intangibles amortization	824	990
Communications	321	417
Advertising	298	521
Other real estate expense	113	2,649
Other	3,691	2,239
Total noninterest expense	34,919	32,401
INCOME BEFORE INCOME TAXES	21,876	4,359
Provision for income taxes	3,866	843
NET INCOME	$ 18,010	$ 3,516
EARNINGS PER SHARE:
Basic	$ 0.89	$ 0.17
Diluted	0.89	0.17
DIVIDENDS PER SHARE	$ 0.12	$ 0.10
Deposit Account, Nonsufficient Funds Fee
NONINTEREST INCOME:
Revenue from contract with customer	$ 83	$ 169
Deposit Account, Service Charge Fee
NONINTEREST INCOME:
Revenue from contract with customer	$ 388	$ 457

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 18,010	$ 3,516
Unrealized (loss) gain on securities:
Change in unrealized holding (loss) gain on available for sale securities during the period	(14,710)	3,466
Reclassification of gain realized through the sale of securities	(49)	(194)
Change in fair value of cash flow hedge	1,824
Total other comprehensive (loss) income	(12,935)	3,272
Deferred tax expense related to other comprehensive income	2,717	(686)
Other comprehensive (loss) income, net of tax	(10,218)	2,586
Comprehensive income	$ 7,792	$ 6,102

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Capital Surplus	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2019	$ 709,865	$ 20,524	$ 521,066	$ 163,375	$ 4,900
Balance (in shares) at Dec. 31, 2019	20,523,816
Net income	$ 3,516			3,516
Other comprehensive income (loss)	2,586				2,586
Cash dividends declared	(2,033)			(2,033)
Common stock issued in connection with the exercise of stock options and restricted stock awards	$ 1,157	75	1,082
Common stock issued in connection with the exercise of stock options and restricted stock awards (in shares)	75,638
Repurchase of common stock	$ (9,302)	(244)	(9,058)
Repurchase of common stock (in shares)	(244,334)
Stock based compensation expense	$ 804		804
Balance at Mar. 31, 2020	$ 706,593	20,355	513,894	164,858	7,486
Balance (in shares) at Mar. 31, 2020	20,355,120
Balance at Dec. 31, 2020	$ 758,669	20,208	508,794	195,236	34,431
Balance (in shares) at Dec. 31, 2020	20,208,323
Net income	$ 18,010			18,010
Other comprehensive income (loss)	(10,218)				(10,218)
Cash dividends declared	(2,412)			(2,412)
Common stock issued in connection with the exercise of stock options and restricted stock awards	$ 1,327	136	1,191
Common stock issued in connection with the exercise of stock options and restricted stock awards (in shares)	135,854
Repurchase of common stock	$ (5,659)	(161)	(5,498)
Repurchase of common stock (in shares)	(161,206)
Stock based compensation expense	$ 820		820
Balance at Mar. 31, 2021	$ 760,537	$ 20,183	$ 505,307	$ 210,834	$ 24,213
Balance (in shares) at Mar. 31, 2021	20,182,971

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Unaudited) (Parentheticals) - $ / shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Retained Earnings
Per share amount of cash dividends declared	$ 0.12	$ 0.10

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 18,010	$ 3,516
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and core deposit intangibles amortization	1,858	1,856
Provision for credit losses	639	10,990
Deferred income tax benefit	(1,899)	(2,250)
Net amortization of premium on investments	1,471	506
Excess tax benefit from stock based compensation	(251)	(25)
Bank owned life insurance income	(139)	(151)
Net accretion of discount on loans	(97)	(1,149)
Net amortization of discount on subordinated debt	28	28
Net accretion of discount on certificates of deposit	(58)	(110)
Loss on sale or write-downs of other real estate and other repossessed assets	1,493	2,283
Net gain on sale of securities	(49)	(194)
Federal Home Loan Bank stock dividends	(19)	(71)
Stock based compensation expense	820	804
Net change in operating leases	712	636
Increase in accrued interest receivable and other assets	(8,012)	(4,141)
Increase (decrease) in accrued interest payable and other liabilities	6,739	(2,118)
Net cash provided by operating activities	21,246	10,410
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from maturities and principal paydowns of available for sale securities	1,012,785	164,575
Proceeds from sales and calls of available for sale securities	4,898	29,735
Purchase of available for sale securities	(1,048,261)	(309,922)
Net change in total loans	(167,253)	(49,052)
Purchase of bank premises and equipment	(916)	(1,510)
Proceeds from sale of bank premises, equipment and other real estate	8,044	485
Net redemptions of Federal Home Loan Bank stock		(6,485)
Net cash used in investing activities	(190,703)	(172,174)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase (decrease) in noninterest-bearing deposits	209,554	(34,700)
Net increase (decrease) in interest-bearing deposits	176,211	(79,717)
Net change in other borrowed funds		100,000
Net (paydown) increase in borrowings under credit agreement	(8,000)	15,000
Dividends paid to common shareholders	(2,412)	(2,033)
Proceeds from the issuance of common stock and stock option exercises	1,327	1,157
Repurchase of common stock	(5,659)	(9,302)
Net cash provided by (used in) financing activities	371,021	(9,595)
NET CHANGE IN CASH AND CASH EQUIVALENTS	201,564	(171,359)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	422,766	346,248
CASH AND CASH EQUIVALENTS, END OF PERIOD	624,330	174,889
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid	5,969	12,932
Cash paid for operating lease liabilities	870	817
SUPPLEMENTAL NONCASH DISCLOSURE:
Lease right-of-use asset obtained in exchange for lessee operating lease liabilities	502
Loans transferred to other real estate		4,280
Other real estate transferred to loans	$ 8,125	1,615
Security trades not yet settled		$ 16,939

NATURE OF OPERATIONS AND SUMMAR

NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING AND REPORTING POLICIES	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING AND REPORTING POLICIES	1. NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING AND REPORTING POLICIES Nature of Operations -Allegiance Bancshares, Inc. (“Allegiance”) and its wholly-owned subsidiary, Allegiance Bank, (the “Bank”, and together with Allegiance, collectively referred to as the “Company”) provide commercial and retail loans and commercial banking services. The Company derives substantially all of its revenues and income from the operation of the Bank. The Company is focused on delivering a wide variety of relationship-driven commercial banking products and community-oriented services tailored to meet the needs of small to medium-sized businesses, professionals and individual customers. The Company operated 27 full-service banking locations in the Houston region, which it defines as the Houston-The Woodlands-Sugar Land and Beaumont-Port Arthur metropolitan statistical areas, with 26 bank offices in the Houston metropolitan area and one bank office location in Beaumont, just outside of the Houston metropolitan area as of March 31, 2021. The Bank provides its customers with a variety of banking services including checking accounts, savings accounts and certificates of deposit, and its primary lending products are commercial, personal, automobile, mortgage and home improvement loans. The Bank also offers safe deposit boxes, automated teller machines, drive-through services and 24-hour depository facilities. Basis of Presentation -The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") for interim financial information and in accordance with guidance provided by the Securities and Exchange Commission. Accordingly, the condensed consolidated financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments considered necessary for a fair presentation of the financial position, results of operations and cash flows of the Company on a consolidated basis, and all such adjustments are of a normal recurring nature. Transactions between the Company and the Bank have been eliminated. The condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021. Significant Accounting and Reporting Policies The Company’s significant accounting and reporting policies can be found in Note 1 of the Company’s annual financial statements included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. New Accounting Standards Adoption of New Accounting Standards ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU 2019-12”), that removes certain exceptions for investments, intraperiod allocations and interim calculations, and adds guidance to reduce complexity in accounting for income taxes. ASU 2019-12 introduces the following new guidance: i) guidance to evaluate whether a step-up in tax basis of goodwill relates to a business combination in which book goodwill was recognized or a separate transaction and ii) a policy election to not allocate consolidated income taxes when a member of a consolidated tax return is not subject to income tax. Additionally, ASU 2019-12 changes the following current guidance: i) making an intraperiod allocation, if there is a loss in continuing operations and gains outside of continuing operations, ii) determining when a deferred tax liability is recognized after an investor in a foreign entity transitions to or from the equity method of accounting, iii) accounting for tax law changes and year-to-date losses in interim periods, and iv) determining how to apply the income tax guidance to franchise taxes that are partially based on income. The Company adopted ASU 2019-12 on January 1, 2021, which did not have a material impact on the Company’s results of operations, financial position or disclosures. ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASC Topic 326”) , was issued by the FASB in June 2016 along with subsequent amendments thereto, which introduce the current expected credit losses (“CECL”) methodology. The measurement of expected credit losses under the CECL methodology utilizes a lifetime “expected credit loss” measurement objective for the recognition of credit losses for loans, held-to-maturity debt securities measured at amortized cost. ASC Topic 326 also applies to off-balance sheet credit exposures. This methodology replaces the multiple existing impairment methods in current guidance, which generally require that a loss be incurred before it is recognized. Within the life cycle of a loan or other financial asset, this new guidance will generally result in the earlier recognition of the provision for credit losses and the related allowance for credit losses than previous practice. For available for sale debt securities that the Company intends to hold and where fair value is less than cost, credit-related impairment, if any, will be recognized through an allowance for credit losses and adjusted each period for changes in credit risk. CECL became effecti ve for the Company on January 1 ; however, o n March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) was signed in to law by the President of the United States and allowed the option to temporarily defer or suspend the adoption of ASC Topic 326. The Company elected to temporarily defer the adoption of CECL due to the uncertainty of the impact of COVID-19 and the volatility of crude oil prices, which can be impactful to the Houston market. During the deferral, t he Company calculated and recorded its provision for loan losses under the incurred loss model that existed prior to ASC Topic 326. The Company adopted the new standard as of January 1, 2020 , dur ing the fourth quarter of 2020 , using the modified retrospective method such that prior period amounts were not adjusted, but were reported in accordance with p reviously applicable generally accepted accounting principles and a cumulative effect adjustment to the opening balance of retained earnings was recognized . Upon adoption of ASC Topic 326, the Company recognized an increase in allowance for credit losses on loans of $3.1 million and the establishment of an allowance for credit losses for off-balance sheet exposure of $3.9 million and a corresponding decrease in retained earnings of $5.5 million, after-tax. The Company adopted ASC Topic 326 using the prospective transition approach for purchased credit deteriorated (“PCD”) loans, which did not require re-evaluation of whether loans previously classified as purchased credit impaired (“PCI”) loans met the criteria of PCD assets at the date of adoption. The Company recognized an increase in the allowance for credit losses for loans of $2.1 million, due to the reclass of PCD discounts previously classified as PCI with a corresponding adjustment to the gross carrying amount of the loans. The remaining noncredit discount was accreted into interest income at the effective interest rate as of January 1, 2020. See Note 5 “Loans and Allowance for Credit Losses” for additional information. The following table illustrates the impact of adopting ASC Topic 326: As of January 1, 2020 As Reported Under ASC Topic 326 Pre-ASC Topic 326 Adoption Impact of ASC Topic 326 Adoption (Dollars in thousands) Assets: Allowance for credit losses on loans: Commercial and industrial $ 15,840 $ 8,818 $ 7,022 Mortgage warehouse — — — Paycheck Protection Program (PPP) — — — Real estate: Commercial real estate (including multi-family residential) 6,007 11,170 (5,163 ) Commercial real estate construction and land development 6,051 4,421 1,630 1-4 family residential (including home equity) 5,452 3,852 1,600 Residential construction 1,056 1,057 (1 ) Consumer and other 257 120 137 Allowance for credit losses on loans $ 34,663 $ 29,438 $ 5,225 Liabilities: Allowance for credit losses on unfunded commitments $ 3,866 $ — $ 3,866 ASC Topic 326 also requires expected credit losses on available for sale (“AFS”) debt securities to be recorded as an allowance for credit losses. For certain types of debt securities, such as U.S. Treasuries and other securities with government guarantees, entities may expect zero credit losses. The zero-loss expectation generally applies to the Company’s securities and no allowance for credit losses were recorded on its AFS securities portfolio at transition. See Note 4 “Securities” for additional information. Newly Issued But Not Yet Effective Accounting Standards ASU 2020-04, "Reference Rate Reform: Facilitation of the Effects of Reference Rate Reform on Financial Reporting - Accounting Standards Codification (“ASC”) Topic 848." ASU 2020-04 provides optional expedients and exceptions for applying GAAP to loan and lease agreements, derivative contracts, and other transactions affected by the anticipated transition away from LIBOR toward new interest rate benchmarks. The guidance allows for companies to: (i) account for certain contract modifications as a continuation of the existing contract without additional analysis; (ii) continue hedge accounting when certain critical terms of a hedging relationship change and assess effectiveness in ways that disregard certain potential sources of ineffectiveness; and (iii) make a one-time sale and/or transfer of certain debt securities from held-to-maturity to available for sale or trading. This ASU is available for adoption effective March 12, 2020 through December 31, 2022. An entity may elect to apply ASU 2020-04 for contract modifications as of January 1, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. Once elected for a Topic or an Industry Subtopic within ASU 2020-04, the amendments must be applied prospectively for all eligible contract modifications for that Topic or Industry Subtopic. The one-time election to sell and/or transfer debt securities classified as held-to-maturity may be made at any time after March 12, 2020. The Company anticipates this ASU will simplify any modifications it executes between the selected start date (yet to be determined) and December 31, 2022 that are directly related to the LIBOR transition by allowing prospective recognition of the continuation of the contract, rather than extinguishment of the old contract resulting in writing off unamortized fees and costs. ASU 2020-04 is not expected to have a significant impact on the Company’s financial statements.

ACQUISITIONS

ACQUISITIONS	3 Months Ended
	Mar. 31, 2021
Business Combinations [Abstract]
ACQUISITIONS	2. ACQUISITIONS Acquisitions are accounted for using the acquisition method of accounting. Accordingly, the assets and liabilities of an acquired entity are recorded at their fair value at the acquisition date. The excess of the purchase price over the estimated fair value of the net assets is recorded as goodwill. The results of operations for an acquisition would be included in the Company’s consolidated financial results beginning on the respective acquisition date. The measurement period for the Company to determine the fair values of acquired identifiable assets and assumed liabilities will end at the earlier of (1) twelve months from the date of the acquisition or (2) as soon as the Company receives the information it was seeking about facts and circumstances that existed as of the acquisition date or learns that more information is not obtainable.

GOODWILL AND CORE DEPOSIT INTAN

GOODWILL AND CORE DEPOSIT INTANGIBLE ASSETS	3 Months Ended
	Mar. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
GOODWILL AND CORE DEPOSIT INTANGIBLE ASSETS	3. GOODWILL AND CORE DEPOSIT INTANGIBLE ASSETS Changes in the carrying amount of the Company’s goodwill and core deposit intangible assets were as follows: Core Deposit Goodwill Intangibles (Dollars in thousands) Balance as of December 31, 2019 $ 223,642 $ 21,876 Amortization — (3,922 ) Balance as of December 31, 2020 223,642 17,954 Amortization — (824 ) Balance as of March 31, 2021 $ 223,642 $ 17,130 Goodwill is recorded on the acquisition date of an entity. During the measurement period, the Company may record subsequent adjustments to goodwill for provisional amounts recorded at the acquisition date. Management performs an evaluation annually, and more frequently if a triggering event occurs, of whether any impairment of the goodwill and other intangible assets has occurred. If any such impairment is determined, a write-down is recorded. As of March 31, 2021, there were no impairments recorded on goodwill and other intangible assets. The estimated aggregate future amortization expense for core deposit intangible assets remaining as of March 31, 2021 is as follows (dollars in thousands): Remaining 2021 $ 2,472 2022 3,003 2023 2,323 2024 2,188 2025 2,061 Thereafter 5,083 Total $ 17,130

SECURITIES

SECURITIES	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
SECURITIES	4. SECURITIES The amortized cost and fair value of investment securities were as follows: March 31, 2021 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value (Dollars in thousands) Available for Sale U.S. government and agency securities $ 24,412 $ 580 $ — $ 24,992 Municipal securities 423,389 25,493 (2,881 ) 446,001 Agency mortgage-backed pass-through securities 172,034 3,204 (1,565 ) 173,673 Agency collateralized mortgage obligations 78,905 3,378 (246 ) 82,037 Corporate bonds and other 58,688 2,187 (62 ) 60,813 Total $ 757,428 $ 34,842 $ (4,754 ) $ 787,516 December 31, 2020 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value (Dollars in thousands) Available for Sale U.S. government and agency securities $ 25,545 $ 654 $ — $ 26,199 Municipal securities 392,586 35,079 (60 ) 427,605 Agency mortgage-backed pass-through securities 167,606 3,829 (146 ) 171,289 Agency collateralized mortgage obligations 80,182 4,263 (75 ) 84,370 Corporate bonds and other 62,124 1,352 (49 ) 63,427 Total $ 728,043 $ 45,177 $ (330 ) $ 772,890 As of March 31, 2021, no The amortized cost and fair value of investment securities at March 31, 2021, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities if borrowers have the right to call or prepay obligations at any time with or without call or prepayment penalties. Amortized Fair Cost Value (Dollars in thousands) Due in one year or less $ 805 $ 807 Due after one year through five years 14,279 14,910 Due after five years through ten years 117,273 121,338 Due after ten years 374,132 394,751 Subtotal 506,489 531,806 Agency mortgage-backed pass through and collateralized mortgage obligation securities 250,939 255,710 Total $ 757,428 $ 787,516 Securities with unrealized losses segregated by length of time such securities have been in a continuous loss position are as follows: March 31, 2021 Less than 12 Months More than 12 Months Total Estimated Unrealized Estimated Unrealized Estimated Unrealized Fair Value Losses Fair Value Losses Fair Value Losses (Dollars in thousands) Available for Sale Municipal securities $ 88,124 $ (2,881 ) $ — $ — $ 88,124 $ (2,881 ) Agency mortgage-backed pass-through securities 92,920 (1,565 ) — — 92,920 (1,565 ) Agency collateralized mortgage obligations 11,842 (212 ) 4,074 (34 ) 15,916 (246 ) Corporate bonds and other 6,841 (62 ) — — 6,841 (62 ) Total $ 199,727 $ (4,720 ) $ 4,074 $ (34 ) $ 203,801 $ (4,754 ) December 31, 2020 Less than 12 Months More than 12 Months Total Estimated Unrealized Estimated Unrealized Estimated Unrealized Fair Value Losses Fair Value Losses Fair Value Losses (Dollars in thousands) Available for Sale Municipal securities $ 8,844 $ (60 ) $ — $ — $ 8,844 $ (60 ) Agency mortgage-backed pass-through securities 28,659 (146 ) — — 28,659 (146 ) Agency collateralized mortgage obligations 11,629 (39 ) 4,203 (36 ) 15,832 (75 ) Corporate bonds and other 15,951 (49 ) — — 15,951 (49 ) Total $ 65,083 $ (294 ) $ 4,203 $ (36 ) $ 69,286 $ (330 ) The Company sold $4.9 million of securities recording gross gains of $49 thousand for the three months ended March 31, 2021. The Company sold $29.7 million of securities and recorded gross gains of $298 thousand and gross losses of $104 thousand for a net gain of $194 thousand during the three months ended March 31, 2020. At March 31, 2021 and December 31, 2020, the Company did not own securities of any one issuer, other than the U.S government and its agencies, in an amount greater than 10% of consolidated shareholders’ equity at such respective dates. The carrying value of pledged securities was $18.5 million at March 31, 2021 and December 31, 2020. The majority of the securities were pledged to collateralize public fund deposits.

LOANS AND ALLOWANCE FOR CREDIT

LOANS AND ALLOWANCE FOR CREDIT LOSSES	3 Months Ended
	Mar. 31, 2021
Loans And Allowance For Credit Losses [Abstract]
LOANS AND ALLOWANCE FOR CREDIT LOSSES	5. LOANS AND ALLOWANCE FOR CREDIT LOSSES The loan portfolio balances, net of unearned income and fees, consist of various types of loans primarily made to borrowers located within Texas and are classified by major type as follows: March 31, 2021 December 31, 2020 (Dollars in thousands) Commercial and industrial $ 664,792 $ 667,079 Paycheck Protection Program (PPP) 728,424 569,901 Real estate: Commercial real estate (including multi-family residential) 2,018,853 1,999,877 Commercial real estate construction and land development 386,637 367,213 1-4 family residential (including home equity) 726,228 737,605 Residential construction 119,528 127,522 Consumer and other 14,707 22,567 Total loans 4,659,169 4,491,764 Allowance for credit losses on loans (52,758 ) (53,173 ) Loans, net $ 4,606,411 $ 4,438,591 Nonaccrual and Past Due Loans An aging analysis of the recorded investment in past due loans, segregated by class of loans, is included below. For purposes of this and future disclosures recorded investment has been defined as the outstanding loan balances including net deferred loan fees, and excluding accrued interest receivable of $33.5 million and $34.5 million as of March 31, 2021 and December 31, 2020, respectively, due to immateriality. March 31, 2021 Loans Past Due and Still Accruing 30-89 90 or More Total Past Nonaccrual Current Total Days Days Due Loans Loans Loans Loans (Dollars in thousands) Commercial and industrial $ 3,941 $ — $ 3,941 $ 14,059 $ 646,792 $ 664,792 Paycheck Protection Program (PPP) — — — — 728,424 728,424 Real estate: Commercial real estate (including multi-family residential) 8,712 — 8,712 13,455 1,996,686 2,018,853 Commercial real estate construction and land development 5,691 — 5,691 1,000 379,946 386,637 1-4 family residential (including home equity) 2,488 — 2,488 5,736 718,004 726,228 Residential construction 324 — 324 — 119,204 119,528 Consumer and other 6 — 6 801 13,900 14,707 Total loans $ 21,162 $ — $ 21,162 $ 35,051 $ 4,602,956 $ 4,659,169 December 31, 2020 Loans Past Due and Still Accruing 30-89 90 or More Total Past Nonaccrual Current Total Days Days Due Loans Loans Loans Loans (Dollars in thousands) Commercial and industrial $ 2,486 $ — $ 2,486 $ 10,747 $ 653,846 $ 667,079 Paycheck Protection Program (PPP) — — — — 569,901 569,901 Real estate: Commercial real estate (including multi-family residential) 3,063 — 3,063 10,081 1,986,733 1,999,877 Commercial real estate construction and land development 2,930 — 2,930 3,011 361,272 367,213 1-4 family residential (including home equity) 3,000 — 3,000 4,525 730,080 737,605 Residential construction — — — — 127,522 127,522 Consumer and other 46 — 46 529 21,992 22,567 Total loans $ 11,525 $ — $ 11,525 $ 28,893 $ 4,451,346 $ 4,491,764 Credit Quality Indicators The Company categorizes loans into risk categories based on relevant information about the ability of borrowers to service their debt. The Company utilizes a risk rating matrix to assign a risk rating to each of its loans. Loans are rated on a scale of 1 to 9. Risk ratings are updated on an ongoing basis and are subject to change by continuous loan monitoring processes including lending management monitoring, executive management and board committee oversight, and independent credit review. including trends related to (i) the weighted-average risk The following is a general description of the risk ratings used: Watch —Loans classified as watch loans may still be of high quality, but have an element of risk added to the credit such as declining payment history, deteriorating financial position of the borrower or a decrease in collateral value. Special Mention —Loans classified as special mention have a potential weakness that deserves management’s close attention. If left uncorrected, these potential weaknesses may result in deterioration of the repayment prospects for the loan or of the institution’s credit position at some future date. They are characterized by the distinct possibility that the institution will sustain some loss if the deficiencies are not corrected. Substandard —Loans classified as substandard have well-defined weaknesses on a continuing basis and are inadequately protected by the current net worth and paying capacity of the borrower, declining collateral values, or a continuing downturn in their industry which is reducing their profits to below zero and having a significantly negative impact on their cash flow. These loans so classified are characterized by the distinct possibility that the institution will sustain some loss if the deficiencies are not corrected. Doubtful —Loans classified as doubtful have all the weaknesses inherent in those classified as substandard with the added characteristic that the weaknesses make collection or liquidation in full on the basis of currently existing facts, conditions and values, highly questionable and improbable. Loss —Loans classified as loss are to be charged-off or charged-down when payment is acknowledged to be uncertain or when the timing or value of payments cannot be determined. “Loss” is not intended to imply that the loan or some portion of it will never be paid, nor does it in any way imply that there has been a forgiveness of debt . The following table presents risk ratings by category of loan as of March 31, 2021 and December 31, 2020: As of March 31, 2021 As of December 31, 2020 Term Loans Amortized Cost Basis by Origination Year 2021 2020 2019 2018 2017 Prior Revolving Loans Revolving Loans Converted to Term Loans Total Total (Dollars in thousands) Commercial and industrial Pass $ 42,316 $ 130,986 $ 74,052 $ 45,122 $ 17,573 $ 25,166 $ 235,233 $ — $ 570,448 $ 562,518 Watch 4,886 8,079 5,314 4,381 1,198 1,839 15,629 — 41,326 41,026 Special Mention 784 1,151 2,663 1,798 1,105 2,487 6,148 — 16,136 25,010 Substandard 4,629 11,859 3,007 3,157 4,829 1,245 7,932 — 36,658 38,385 Doubtful — 213 — 11 — — — — 224 140 Total commercial and industrial loans $ 52,615 $ 152,288 $ 85,036 $ 54,469 $ 24,705 $ 30,737 $ 264,942 $ — $ 664,792 $ 667,079 Paycheck Protection Program (PPP) Pass $ 331,736 $ 396,538 $ — $ — $ — $ 150 $ — $ — $ 728,424 $ 569,901 Watch — — — — — — — — — — Special Mention — — — — — — — — — — Substandard — — — — — — — — — — Doubtful — — — — — — — — — — Total PPP loans $ 331,736 $ 396,538 $ — $ — $ — $ 150 $ — $ — $ 728,424 $ 569,901 Commercial real estate (including multi-family residential) Pass $ 153,677 $ 586,634 $ 296,323 $ 200,738 $ 190,080 $ 212,707 $ 47,193 $ — $ 1,687,352 $ 1,629,023 Watch 6,612 25,111 39,322 17,722 23,039 36,873 1,956 — 150,635 177,651 Special Mention 6,115 11,053 8,007 6,003 10,328 14,462 647 — 56,615 68,276 Substandard 2,909 21,312 24,711 17,806 23,616 31,344 2,553 — 124,251 124,927 Doubtful — — — — — — — — — — Total commercial real estate (including multi-family residential) loans $ 169,313 $ 644,110 $ 368,363 $ 242,269 $ 247,063 $ 295,386 $ 52,349 $ — $ 2,018,853 $ 1,999,877 Commercial real estate construction and land development Pass $ 39,047 $ 171,318 $ 61,948 $ 29,238 $ 13,064 $ 8,001 $ 14,375 $ — $ 336,991 $ 320,133 Watch 1,214 17,351 3,466 3,253 6,332 2,606 — — 34,222 39,021 Special Mention 523 2,091 2,967 374 911 261 113 — 7,240 2,880 Substandard — 5,983 966 680 — — 555 — 8,184 5,179 Doubtful — — — — — — — — — — Total commercial real estate construction and land development $ 40,784 $ 196,743 $ 69,347 $ 33,545 $ 20,307 $ 10,868 $ 15,043 $ — $ 386,637 $ 367,213 1-4 family residential (including home equity) Pass $ 55,339 $ 199,484 $ 111,305 $ 89,416 $ 60,582 $ 61,211 $ 84,886 $ — $ 662,223 $ 670,074 Watch 3,108 11,833 3,110 4,135 5,660 4,300 4,455 — 36,601 37,667 Special Mention — 2,387 1,472 4,284 390 4,757 2,453 — 15,743 18,790 Substandard — 1,375 2,527 3,073 1,499 2,969 218 — 11,661 11,074 Doubtful — — — — — — — — — — Total 1-4 family residential (including home equity) $ 58,447 $ 215,079 $ 118,414 $ 100,908 $ 68,131 $ 73,237 $ 92,012 $ — $ 726,228 $ 737,605 As of March 31, 2021 As of December 31, 2020 Term Loans Amortized Cost Basis by Origination Year 2021 2020 2019 2018 2017 Prior Revolving Loans Revolving Loans Converted to Term Loans Total Total (Dollars in thousands) Residential construction Pass $ 16,204 $ 85,597 $ 6,971 $ 5,266 $ 730 $ 730 $ — $ — $ 115,498 $ 124,737 Watch 50 2,584 742 — — — — — 3,376 2,785 Special Mention — 654 — — — — — — 654 — Substandard — — — — — — — — — — Doubtful — — — — — — — — — — Total residential construction $ 16,254 $ 88,835 $ 7,713 $ 5,266 $ 730 $ 730 $ — $ — $ 119,528 $ 127,522 Consumer and other Pass (1) $ (11,511 ) $ 16,325 $ 2,469 $ 1,360 $ 485 $ 130 $ 4,027 $ — $ 13,285 $ 21,359 Watch — 53 161 3 — — 63 — 280 389 Special Mention — 224 — 33 — — 3 — 260 270 Substandard — 470 300 39 73 — — — 882 549 Doubtful — — — — — — — — — — Total consumer and other $ (11,511 ) $ 17,072 $ 2,930 $ 1,435 $ 558 $ 130 $ 4,093 $ — $ 14,707 $ 22,567 Total loans Pass $ 626,808 $ 1,586,882 $ 553,068 $ 371,140 $ 282,514 $ 308,095 $ 385,714 $ — $ 4,114,221 $ 3,897,745 Watch 15,870 65,011 52,115 29,494 36,229 45,618 22,103 — 266,440 298,539 Special Mention 7,422 17,560 15,109 12,492 12,734 21,967 9,364 — 96,648 115,226 Substandard 7,538 40,999 31,511 24,755 30,017 35,558 11,258 — 181,636 180,114 Doubtful — 213 — 11 — — — — 224 140 Total loans $ 657,638 $ 1,710,665 $ 651,803 $ 437,892 $ 361,494 $ 411,238 $ 428,439 $ — $ 4,659,169 $ 4,491,764 (1) Includes net deferred fees of $22.0 million and $13.9 million on PPP loans as of March 31, 2021 and December 31, 2020, respectively. The following table presents the activity in the allowance for credit losses on loans by portfolio type for the three months ended March 31, 2021 and 2020: Commercial and Paycheck Protection Program (PPP) Commercial real estate (including multi-family residential) Commercial real estate construction and land development 1-4 family residential (including home equity) Residential construction Consumer and other Total (Dollars in thousands) Allowance for credit losses on loans: Three Months Ended Balance December 31, 2020 $ 17,738 $ — $ 23,934 $ 6,939 $ 3,279 $ 870 $ 413 $ 53,173 Provision for loan losses 1,304 — (155 ) 683 (1,723 ) (45 ) (134 ) (70 ) Charge-offs (404 ) — — — — — — (404 ) Recoveries 59 — — — — — — 59 Net charge-offs (345 ) — — — — — — (345 ) Balance March 31, 2021 $ 18,697 $ — $ 23,779 $ 7,622 $ 1,556 $ 825 $ 279 $ 52,758 Allowance for loan losses: Three Months Ended Balance December 31, 2019 $ 8,818 $ — $ 11,170 $ 4,421 $ 3,852 $ 1,057 $ 120 $ 29,438 Provision for loan losses 1,865 — 5,725 732 2,296 374 (2 ) 10,990 Charge-offs (734 ) — (144 ) (2,164 ) (90 ) — — (3,132 ) Recoveries 215 — — — — — — 215 Net charge-offs (519 ) — (144 ) (2,164 ) (90 ) — — (2,917 ) Balance March 31, 2020 $ 10,164 $ — $ 16,751 $ 2,989 $ 6,058 $ 1,431 $ 118 $ 37,511 Allowance for Credit Losses on Unfunded Commitments . In addition to the allowance for credit losses on loans, the Company has established an allowance for credit losses on unfunded commitments, classified in other liabilities and adjusted as a provision for credit loss expense. The allowance represents estimates of expected credit losses over the contractual period in which there is exposure to credit risk via a contractual obligation to extend credit, unless that obligation is unconditionally cancellable by the Company. The estimate includes consideration of the likelihood that funding will occur and an estimate of expected credit losses on the commitments expected to fund. The estimate of commitments expected to fund is informed by historical analysis looking at utilization rates. The expected credit loss rates applied to the commitments expected to fund is informed by the general valuation allowance utilized for outstanding balances with the same underlying assumptions and drivers. The allowance for credit losses on unfunded commitments as of March 31, 2021 and December 31, 2020 was $5.4 million and $4.7 million, respectively. The establishment of an allowance as of December 31, 2020 was due to the adoption of CECL and as such was not considered at March 31, 2020. This reserve is maintained at a level management believes to be sufficient to absorb losses arising from unfunded loan commitments. The following table details activity in the allowance for credit losses on unfunded commitments as of March 31, 2021 is as follows (dollars in thousands): Balance at December 31, 2020 $ 4,697 Provision for credit losses on unfunded commitments 709 Balance at March 31, 2021 $ 5,406 Collateral dependent loans are secured by commercial real estate assets, accounts receivable, inventory and equipment. For a collateral dependent loan, the Company’s evaluation process includes a valuation by appraisal or other collateral analysis adjusted for selling costs, when appropriate. This valuation is compared to the remaining outstanding principal balance of the loan. If a loss is determined to be probable, the loss is included in the allowance for credit losses on loans as a specific allocation As of March 31, 2021 Real Estate Business Assets Other Total (Dollars in thousands) Commercial and industrial $ — $ 8,619 $ — $ 8,619 Paycheck Protection Program (PPP) — — — — Real estate: Commercial real estate (including multi-family residential) 707 — — 707 Commercial real estate construction and land development 1,000 — — 1,000 1-4 family residential (including home equity) 5,572 — — 5,572 Residential construction — — — — Consumer and other — — 280 280 Total $ 7,279 $ 8,619 $ 280 $ 16,178 As of December 31, 2020 Real Estate Business Assets Other Total (Dollars in thousands) Commercial and industrial $ — $ 5,157 $ — $ 5,157 Paycheck Protection Program (PPP) — — — — Real estate: Commercial real estate (including multi-family residential) 425 — — 425 Commercial real estate construction and land development — — — — 1-4 family residential (including home equity) 3,101 — — 3,101 Residential construction — — — — Consumer and other — — — — Total $ 3,526 $ 5,157 $ — $ 8,683 The following table presents additional information regarding nonaccrual loans. No interest income was recognized on nonaccrual loans as of March 31, 2021 and December 31, 2020. As of March 31, 2021 Nonaccrual Loans with No Related Allowance Nonaccrual Loans with Related Allowance Total Nonaccrual Loans (Dollars in thousands) Commercial and industrial $ 2,906 $ 11,153 $ 14,059 Paycheck Protection Program (PPP) — — — Real estate: Commercial real estate (including multi-family residential) 4,191 9,264 13,455 Commercial real estate construction and land development 1,000 — 1,000 1-4 family residential (including home equity) 5,160 576 5,736 Residential construction — — — Consumer and other 625 176 801 Total loans $ 13,882 $ 21,169 $ 35,051 As of December 31, 2020 Nonaccrual Loans with No Related Allowance Nonaccrual Loans with Related Allowance Total Nonaccrual Loans (Dollars in thousands) Commercial and industrial $ 2,097 $ 8,650 $ 10,747 Paycheck Protection Program (PPP) — — — Real estate: Commercial real estate (including multi-family residential) 7,487 2,594 10,081 Commercial real estate construction and land development 2,958 53 3,011 1-4 family residential (including home equity) 2,652 1,873 4,525 Residential construction — — — Consumer and other — 529 529 Total loans $ 15,194 $ 13,699 $ 28,893 Troubled Debt Restructurings As of March 31, 2021 and December 31, 2020, the Company had a recorded investment in troubled debt restructurings of $25.2 million and $25.8 million, respectively. The Company allocated $2.9 million and $3.3 million of specific reserves for troubled debt restructurings at March 31, 2021 and December 31, 2020, respectively. The following table presents information regarding loans modified in a troubled debt restructuring during the three months ended March 31, 2021 and 2020: Three Months Ended March 31, 2021 2020 Number of Contracts Pre-Modification of Outstanding Recorded Investment Post Modification of Outstanding Recorded Investment Number of Contracts Pre-Modification of Outstanding Recorded Investment Post Modification of Outstanding Recorded Investment (Dollars in thousands) Troubled Debt Restructurings Commercial and industrial — $ — $ — 5 $ 1,104 $ 1,104 Paycheck Protection Program (PPP) — — — — — — Real estate: Commercial real estate (including multi-family residential) 1 545 545 — — — Commercial real estate construction and land development — — — — — — 1-4 family residential (including home equity) — — — 1 118 118 Residential construction — — — — — — Consumer and other — — — 1 30 30 Total 1 $ 545 $ 545 7 $ 1,252 $ 1,252 Troubled debt restructurings resulted in no charge-offs during the three months ended March 31, 2021 and $394 thousand of charge-offs during the three months ended March 31, 2020. As of March 31, 2021, one loan for $174 thousand was modified under a troubled debt restructuring during the previous twelve-month period that subsequently defaulted during the three months ended March 31, 2021. As of March 31, 2020, four loans for a total of $441 thousand were modified under a troubled debt restructuring during the previous twelve-month period that subsequently defaulted during the three months ended March 31, 2020. Default is determined at 90 or more days past due. The modifications primarily related to extending the amortization periods of the loans. The Company did not grant principal reductions on any restructured loans. There were no commitments to lend additional amounts to troubled debt restructured loans for the three months ended March 31, 2021 and 2020. During the three months ended March 31, 2021, the Company added $545 thousand in new troubled debt restructurings, of which $545 thousand was still outstanding on March 31, 2021. During the three months ended March 31, 2020, the Company added $1.3 million in new troubled debt restructurings, of which $1.2 million was still outstanding on March 31, 2020. The Company granted principal and interest deferrals on outstanding loan balances to customers affected by the COVID-19 pandemic. Additionally, upon request and after meeting certain conditions, borrowers could be granted additional payment deferrals subsequent to the first deferral. In addition to the short-term modification program implemented by the Company, Section 4013 of the CARES Act and bank regulatory interagency guidance gave entities temporary relief from the accounting and disclosure requirements for troubled debt restructurings (“TDR”) indicating that a lender could conclude that the modifications are not a TDR if the borrower was less than 30 days past due as of December 31, 2019. The following table presents information regarding principal and interest deferrals as of March 31, 2021 associated with loan modifications related to COVID-19: Initial Deferrals Additional Deferrals Remaining Deferrals Outstanding Loan Balance Deferred Loan Balance Percentage of Total Deferrals Deferred Loan Balance Percentage of Total Deferrals Deferred Loan Balance Percentage of Total Deferrals (Dollars in thousands) Commercial and industrial $ 664,792 $ 109,866 10.3 % $ 22,134 9.3 % $ 6,398 10.3 % Paycheck Protection Program (PPP) 728,424 — 0.0 % — 0.0 % — 0.0 % Real estate: Commercial real estate (including multi-family residential) 2,018,853 761,179 71.5 % 182,662 76.8 % 48,646 78.3 % Commercial real estate construction and land development 386,637 81,566 7.7 % 19,991 8.4 % 2,613 4.2 % 1-4 family residential (including home equity) 726,228 108,870 10.2 % 12,700 5.3 % 4,463 7.2 % Residential construction 119,528 1,687 0.2 % 161 0.1 % — 0.0 % Consumer and other 14,707 805 0.1 % 157 0.1 % — 0.0 % Total loans $ 4,659,169 $ 1,063,973 100.0 % $ 237,805 100.0 % $ 62,120 100.0 %

LEASES

LEASES	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
LEASES	6. LEASES Lease payments over the expected term are discounted using the Company’s incremental borrowing rate for borrowings of similar terms. Generally, the Company cannot be reasonably certain about whether or not it will renew a lease until such time as the lease is within the last two years of the existing lease term. When the Company is reasonably certain that a renewal option will be exercised, it measures/remeasures the right-of-use asset and related lease liability using the lease payments specified for the renewal period or, if such amounts are unspecified, the Company generally assumes an increase (evaluated on a case-by-case basis in light of prevailing market conditions) in the lease payment over the final period of the existing lease term. There were no sale and leaseback transactions, leveraged leases or lease transactions with related parties during the three months ended March 31, 2021 and 2020. At March 31, 2021, the Company had 15 leases consisting of branch locations and office space. On the March 31, 2021 balance sheet, the right-of-use asset is classified within premises and equipment and the lease liability is included in other liabilities. The Company also owns certain office facilities which it leases to outside parties under operating lessor leases; however, such leases are not significant. All leases were classified as operating leases. Leases with an initial term of 12 months or less are not recorded on the balance sheet an d the related lease expense is recognized on a straight- line basis over the lease term. Certain leases include options to renew, with renewal terms that can extend the lease term from one to five years. Lease assets and liabilities include related options that are reasonably certain of being exercised. The depreciable life of leased assets are limited by the expected lease term. Supplemental lease information at the dates indicated is as follows: March 31, 2021 December 31, 2020 (Dollars in thousands) Balance Sheet: Operating lease right of use asset classified as premises and equipment $ 11,399 $ 11,610 Operating lease liability classified as other liabilities $ 11,625 $ 11,850 Weighted average lease term, in years 5.40 5.56 Weighted average discount rate 2.77 % 2.86 % Lease costs for the dates indicated is as follows: Three Months Ended March 31, 2021 2020 (Dollars in thousands) Income Statement: Operating lease cost $ 873 $ 799 Short-term lease cost 15 36 Sublease income (18 ) (18 ) Total operating lease costs $ 870 $ 817 A maturity analysis of the Company’s lease liabilities is as follows: March 31, 2021 December 31, 2020 (Dollars in thousands) Lease payments due: Within one year $ 3,132 $ 3,068 After one but within two years 2,539 2,664 After two but within three years 2,120 2,056 After three but within four years 1,490 1,591 After four but within five years 1,069 1,057 After five years 2,144 2,355 Total lease payments 12,494 12,791 Discount on cash flows 869 941 Total lease liability $ 11,625 $ 11,850

FAIR VALUE

FAIR VALUE	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
FAIR VALUE	7. FAIR VALUE The Company uses fair value measurements to record fair value adjustments to certain assets and to determine fair value disclosures. Fair value represents the exchange price that would be received from selling an asset or paid to transfer a liability, otherwise known as an “exit price,” in the principal or most advantageous market available to the entity in an orderly transaction between market participants on the measurement date. Fair Value Hierarchy Fair value is the exchange price that would be received for an asset or paid to transfer a liability (exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The Company groups financial assets and financial liabilities measured at fair value in three levels, based on the markets in which the assets and liabilities are traded and the reliability of the assumptions used to determine fair value. These levels are: • Level 1—Quoted prices for identical assets or liabilities in active markets that the entity has the ability to access as of the measurement date. • Level 2—Significant other observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data. • Level 3—Significant unobservable inputs that reflect management’s judgment and assumptions that market participants would use in pricing an asset or liability that are supported by little or no market activity. The carrying amounts and estimated fair values of financial instruments that are reported on the balance sheet are as follows: As of March 31, 2021 Carrying Estimated Fair Value Amount Level 1 Level 2 Level 3 Total (Dollars in thousands) Financial assets Cash and cash equivalents $ 624,330 $ 624,330 $ — $ — $ 624,330 Available for sale securities 787,516 — 787,516 — 787,516 Loans held for investment, net of allowance 4,606,411 — — 4,605,252 4,605,252 Interest rate swap 572 — 572 — 572 Accrued interest receivable 38,632 3 5,133 33,496 38,632 Financial liabilities Deposits $ 5,374,189 $ — $ 5,383,876 $ — $ 5,383,876 Accrued interest payable 3,862 — 3,862 — 3,862 Borrowed funds 147,517 — 132,123 — 132,123 Subordinated debt 108,453 — 109,935 — 109,935 As of December 31, 2020 Carrying Estimated Fair Value Amount Level 1 Level 2 Level 3 Total (Dollars in thousands) Financial assets Cash and cash equivalents $ 422,766 $ 422,766 $ — $ — $ 422,766 Available for sale securities 772,890 — 772,890 — 772,890 Loans held for investment, net of allowance 4,438,591 — — 4,431,816 4,431,816 Accrued interest receivable 40,053 2 5,531 34,520 40,053 Financial liabilities Deposits $ 4,988,482 $ — $ 5,003,594 $ — $ 5,003,594 Interest rate swap 1,252 — 1,252 — 1,252 Accrued interest payable 2,701 — 2,701 — 2,701 Borrowed funds 155,515 — 144,629 — 144,629 Subordinated debt 108,322 — 109,832 — 109,832 The following tables present fair values for assets and liabilities measured at fair value on a recurring basis. There were no liabilities measured at fair value on a recurring basis as of March 31, 2021. March 31, 2021 Level 1 Level 2 Level 3 Total (Dollars in thousands) Financial assets Available for sale securities: U.S. government and agency securities $ — $ 24,992 $ — $ 24,992 Municipal securities — 446,001 — 446,001 Agency mortgage-backed pass-through securities — 173,673 — 173,673 Agency collateralized mortgage obligations — 82,037 — 82,037 Corporate bonds and other — 60,813 — 60,813 Total available for sale securities $ — $ 787,516 $ — $ 787,516 Interest rate swap $ — $ 572 $ — $ 572 December 31, 2020 Level 1 Level 2 Level 3 Total (Dollars in thousands) Financial assets Available for sale securities: U.S. government and agency securities $ — $ 26,199 $ — $ 26,199 Municipal securities — 427,605 — 427,605 Agency mortgage-backed pass-through securities — 171,289 — 171,289 Agency collateralized mortgage obligations — 84,370 — 84,370 Corporate bonds and other — 63,427 — 63,427 Total available for sale securities $ — $ 772,890 $ — $ 772,890 Financial liabilities Interest rate swap $ — $ 1,252 $ — $ 1,252 There were no transfers between levels during the three months ended March 31, 2021 or 2020. Assets measured at fair value on a nonrecurring basis are summarized in the table below. There were no liabilities measured at fair value on a nonrecurring basis at March 31, 2021 and December 31, 2020. As of March 31, 2021 Level 1 Level 2 Level 3 (Dollars in thousands) Collateral Dependent Loans: Commercial and industrial $ — $ — $ 11,153 Commercial real estate (including multi- family residential) — — 9,264 Commercial real estate construction and land development — — — 1-4 family residential (including home equity) — — 576 Residential construction — — — Consumer and other — — 176 Other real estate owned — — 576 $ — $ — $ 21,745 As of December 31, 2020 Level 1 Level 2 Level 3 (Dollars in thousands) Collateral Dependent Loans: Commercial and industrial $ — $ — $ 8,650 Commercial real estate (including multi- family residential) — — 2,594 Commercial real estate construction and land development — — 53 1-4 family residential (including home equity) — — 1,873 Residential construction — — — Consumer and other — — 529 Other real estate owned — — 9,196 $ — $ — $ 22,895 Collateral Dependent Loans Specific Allocation of Allowance for Credit Losses on Loans A loan is considered to be a collateral dependent loan when, based on current information and events, the Company expects repayment of the financial assets to be provided substantially through the operation or sale of the collateral and the Company has determined that the borrower is experiencing financial difficulty as of the measurement date. The allowance for credit losses on loans is measured by estimating the fair value of the loan based on the present value of expected cash flows, the market price of the loan, or the underlying fair value of the loan’s collateral. For real estate loans, fair value of the loan’s collateral is generally determined by third-party appraisals or internal evaluations, which are then adjusted for the estimated selling and closing costs related to liquidation of the collateral. For this asset class, the actual valuation methods (income, sales comparable, or cost) vary based on the status of the project or property. For example, land is generally based on the sales comparable method while construction is based on the income and/or sales comparable methods. The unobservable inputs may vary depending on the individual assets with no one of the three methods being the predominant approach. The Company reviews the third-party appraisal for appropriateness and adjusts the value downward to consider selling and closing costs, which typically range from 5 % to 10 % of the appraised value. For non-real estate loans, fair value of the loan’s collateral may be determined using an appraisal, net book value per the borrower’s financial statements, or aging reports, adjusted or discounted based on management’s historical knowledge, changes in market conditions from the time of the valuation, and management’s expertise and knowledge of the client and client’s business. Other Real Estate Owned Other real estate owned is comprised of real estate acquired in partial or full satisfaction of loans. Other real estate owned is recorded at its estimated fair value less estimated selling and closing costs at the date of transfer. Any excess of the related loan balance over the fair value less expected selling costs is charged to the allowance. Subsequent declines in fair value are reported as adjustments to the carrying amount and are recorded against earnings. The fair value of other real estate owned is determined using third-party appraisals or other indications of value based on recent comparable sales of similar properties or assumptions generally observable in the marketplace. For this asset class, the actual valuation methods (income, sales comparable or cost) vary based on the status of the project or property. For example, land is generally based on the sales comparable method while construction is based on the income and/or sales comparable methods. The unobservable inputs may vary depending on the individual assets with no one of the three methods being the predominant approach. The Company reviews the third party appraisal for appropriateness and adjusts the value downward to consider selling and closing costs, which typically range from 5% to 10% of the appraised value. At March 31, 2021, the $576 thousand balance of other real estate owned consisted of one foreclosed residential property recorded as a result of obtaining physical possession of the property. The Company had $9.2 million of other real estate owned at December 31, 2020 consisting primarily of foreclosed commercial real estate properties and one foreclosed residential property recorded as a result of obtaining physical possession of the property.

DEPOSITS

DEPOSITS	3 Months Ended
	Mar. 31, 2021
Deposit Liabilities [Abstract]
DEPOSITS	8. DEPOSITS Time deposits that met or exceeded the Federal Deposit Insurance Corporation insurance limit of $250 thousand at March 31, 2021 and December 31, 2020 were $782.1 million and $726.8 million, respectively. Scheduled maturities of time deposits for the next five years are as follows (dollars in thousands): Within one year $ 868,760 After one but within two years 367,037 After two but within three years 68,547 After three but within four years 28,664 After four but within five years 28,527 Total $ 1,361,535 The Company had $433.2 million and $453.8 million of brokered deposits as of March 31, 2021 and December 31, 2020, respectively. There were no concentrations of deposits with any one depositor at March 31, 2021 and December 31, 2020.

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS	3 Months Ended
	Mar. 31, 2021
Derivative Instruments And Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	9. DERIVATIVE INSTRUMENTS The Company entered into a financial derivative in 2020. Financial derivatives are reported at fair value in other assets or other liabilities. The accounting for changes in the fair value of a derivative depends on whether it has been designated and qualifies as part of a hedging relationship. Derivatives designated as cash flow hedges For derivative instruments that are designated and qualify as a cash flow hedge, the aggregate fair value of the derivative instrum ent is recorded in other assets or other liabilities with any gain or loss related to changes in fair value recorded in accumulated other comprehensive income, net of tax. The gain or loss is reclassified into earnings in the same period during which the hedged asset or liability affects earnings and is presented in the same income statement line item as the earnings effect of the hedged asset or liability. The Company uses forward cash flow hedges in an effort to manage future interest rate exposure on liabilities. The hedging strategy converts the variable interest rate on liabilities to a fixed interest rate and is used in an effort to protect the Company from floating interest rate variability. A summary of the Company’s cash flow hedge relationship as of March 31, 2021 is as follows: Balance Sheet Location Weighted Average Maturity (In Years) Weighted Average Pay Rate Receive Rate Notional Amount Estimated Fair Value (Dollars in thousands) Liability derivatives Interest rate swaps Other assets 4.02 0.64% 3 month LIBOR $ 100,000 $ 572 The effects of the Company’s cash flow hedge relationship on the statement of comprehensive income during the three months ended March Amount of Loss Recognized in Other Comprehensive Income Three Months Ended March 31, 2021 2020 (Dollars in thousands) Liability derivatives Interest rate swaps $ 1,824 $ — The cash flow hedge was determined to be effective during the periods presented and as a result qualified for hedge accounting treatment. The hedge would no longer be considered effective if a portion of the hedge becomes ineffective, the item hedged is no longer in existence or the Company discontinues hedge accounting. The Company expects the hedge at March March L osses totaling $72 thousand, net of tax, were reclassified from accumulated other comprehensive income into net income during the three months ended March 31, 2021.

BORROWINGS AND BORROWING CAPACI

BORROWINGS AND BORROWING CAPACITY	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
BORROWINGS AND BORROWING CAPACITY	10. BORROWINGS AND BORROWING CAPACITY The Company has an available line of credit with the Federal Home Loan Bank (“FHLB”) of Dallas, which allows the Company to borrow on a collateralized basis. FHLB advances are used to manage liquidity as needed. The advances are secured by a blanket lien on certain loans. Maturing advances are replaced by drawing on available cash, making additional borrowings or through increased customer deposits. At March 31, 2021, the Company had a total borrowing capacity of $2.00 billion, of which $1.33 billion was available and $672.1 million was outstanding. FHLB advances of $140.0 million were outstanding at March 31, 2021, at a weighted average interest rate of 1.19%. Letters of credit were $532.1 million at March 31, 2021, of which $218.5 million will expire during the remaining months of 2021, $258.0 million will expire in 2022, $19.4 million will expire in 2023 and $36.2 million will expire in 2024. On December 28, 2018, the Company amended its revolving credit agreement to increase the maximum commitment to advance funds to $45.0 million which will reduce annually by $7.5 million beginning in December 2020 and on each December 22nd each year thereafter. The Company is required to repay any outstanding balance in excess of the then-current maximum commitment amount. The revised agreement will mature in December 2025 and is secured by 100% of the capital stock of the Bank. At March 31, 2021, the balance of the revolving credit agreement was $7.6 million. The credit agreement contains certain restrictive covenants. At March 31, 2021, the Company believes it was in compliance with all such debt covenants. The interest rate on the debt is the Prime Rate minus 25 basis points, or 3.00%, at March 31, 2021, and is paid quarterly.

SUBORDINATED DEBT

SUBORDINATED DEBT	3 Months Ended
	Mar. 31, 2021
Subordinated Borrowings [Abstract]
SUBORDINATED DEBT	11. SUBORDINATED DEBT Junior Subordinated Debentures On January 1, 2015, the Company acquired F&M Bancshares, Inc. and assumed Farmers & Merchants Capital Trust II and Farmers & Merchants Capital Trust III. Each of these trusts is a capital or statutory business trust organized for the sole purpose of issuing trust securities and investing the proceeds in the Company’s junior subordinated debentures. The preferred trust securities of each trust represent preferred beneficial interests in the assets of the respective trusts and are subject to mandatory redemption upon payment of the junior subordinated debentures held by the trust. The common securities of each trust are wholly owned by the Company. Each trust’s ability to pay amounts due on the trust preferred securities is solely dependent upon the Company making payment on the related junior subordinated debentures. The debentures, which are the only assets of each trust, are subordinate and junior in right of payment to all of the Company’s present and future senior indebtedness. The Company has fully and unconditionally guaranteed each trust’s obligations under the trust securities issued by such trust to the extent not paid or made by such trust, provided such trust has funds available for such obligations. The junior subordinated debentures are included in Tier 1 capital under current regulatory guidelines and interpretations. Under the provisions of each issue of the debentures, the Company has the right to defer payment of interest on the debentures at any time, or from time to time, for periods not exceeding five years. If interest payments on either issue of the debentures are deferred, the distributions on the applicable trust preferred securities and common securities will also be deferred. The Company assumed the junior subordinated debentures with an aggregate original principal amount of $11.3 million and a current carrying value at March 31, 2021 of $9.7 million. At acquisition, the Company recorded a discount of $2.5 million on the debentures. The difference between the carrying value and contractual balance will be recognized as a yield adjustment over the remaining term for the debentures. At March 31, 2021, the Company had $11.3 million outstanding in junior subordinated debentures issued to the Company’s unconsolidated subsidiary trusts. The junior subordinated debentures are included in tier 1 capital under current regulatory guidelines and interpretations. A summary of pertinent information related to the Company’s issues of junior subordinated debentures outstanding at March 31, 2021 is set forth in the table below: Description Issuance Date Trust Preferred Securities Outstanding Interest Rate (1) Junior Subordinated Debt Owed to Trusts Maturity Date (2) (Dollars in thousands) Farmers & Merchants Capital Trust II November 13, 2003 $ 7,500 3 month LIBOR + 3.00% $ 7,732 November 8, 2033 Farmers & Merchants Capital Trust III June 30, 2005 3,500 3 month LIBOR + 1.80% 3,609 July 7, 2035 $ 11,341 (1) The 3-month LIBOR in effect as of March 31, 2021 was 0.18962%. (2) All debentures are currently callable. Subordinated Notes In December 2017, the Bank completed the issuance, through a private placement, of $40.0 million aggregate principal amount of Fixed-to-Floating Rate Subordinated Notes (the "Bank Notes") due December 15, 2027. The Bank Notes were issued at a price equal to 100% of the principal amount, resulting in net proceeds to the Bank of $39.4 million. The Bank Notes bear a fixed interest rate of 5.25% per annum until (but excluding) December 15, 2022, payable semi-annually in arrears. From December 15, 2022, the Bank Notes will bear a floating rate of interest equal to 3-Month LIBOR + 3.03% until the Bank Notes mature on December 15, 2027, or such earlier redemption date, payable quarterly in arrears. The Bank Notes will be redeemable by the Bank, in whole or in part, on or after December 15, 2022 or, in whole but not in part, upon the occurrence of certain specified tax events, capital events or investment company events. Any redemption will be at a redemption price equal to 100% of the principal amount of Bank Notes being redeemed, plus accrued and unpaid interest, and will be subject to, and require, prior regulatory approval. The Bank Notes are not subject to redemption at the option of the holders. In September 2019, the Company completed the issuance of $60.0 million aggregate principal amount of Fixed-to-Floating Rate Subordinated Notes (the "Company Notes") due October 1, 2029. The Company Notes were issued at a price equal to 100% of the principal amount, resulting in net proceeds to the Company of $ million. The Company use d the net proceeds from the offering to support its growth and for general corporate purposes. The Company Notes bear a fixed interest rate of 4.70% per annum until (but excluding) October 1, 2024, payable semi-annually in arrears on April 1 and October 1, commencing on April 1, 2020. Thereafter, from October 1, 2024 through the maturity date, October 1, 2029, or earlier redemption date, the Company Notes will bear interest at a floating rate equal to the then-current three-month LIBOR, plus 313 basis points (3.13%) for each quarterly interest period (subject to certain provisions set forth under “Description of the Notes—Interest Rates and Interest Payment Dates” included in the Prospectus Supplement), payable quarterly in arrears on January 1, April 1, July 1 and October 1 of each year. Any redemption will be at a redemption price equal to 100% of the principal amount of Company Notes being redeemed, plus accrued and unpaid interest, and will be subject to, and require, prior regulatory approval. The Company Notes are not subject to redemption at the option of the holders.

INCOME TAXES

INCOME TAXES	3 Months Ended
	Mar. 31, 2021
Income Tax Disclosure [Abstract]
INCOME TAXES	12. INCOME TAXES The amount of the Company’s federal and state income tax expense is influenced by the amount of pre-tax income, the amount of tax-exempt income and the amount of other nondeductible items. For the three months ended March 31, 2021, income tax expense was $3.9 million compared with $843 thousand for the three months ended March 31, 2020. The effective income tax rate for the three months ended March 31, 2021 was 17.7% compared to 19.3% for the three months ended March 31, 2020. Interest and penalties related to tax positions are recognized in the period in which they begin accruing or when the entity claims the position that does not meet the minimum statutory thresholds. The Company does not have any uncertain tax positions and does not have any interest or penalties recorded in the income statement for the three months ended March 31, 2021. The Company is no longer subject to examination by the U.S. Federal Tax Jurisdiction for the years prior to 2017.

STOCK BASED COMPENSATION

STOCK BASED COMPENSATION	9 Months Ended
	Sep. 30, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
STOCK BASED COMPENSATION	13. STOCK BASED COMPENSATION At March 31, 2021, the Company had two stock-based employee compensation plans with awards outstanding. In connection with the acquisition of Post Oak Bancshares, Inc. on October 1, 2018, the Company assumed the Post Oak Bancshares, Inc. Stock Option Plan, under which no additional awards will be issued. During 2019, the Company’s Board of Directors and shareholders approved the 2019 Amended and Restated Stock Awards and Incentive Plan (the “Plan”) covering certain awards of stock-based compensation to key employees and directors of the Company. Under the Plan, the Company is authorized to issue a maximum aggregate of 3,200,000 shares of stock, up to 1,800,000 of which may be issued through incentive stock options. The Company accounts for stock based employee compensation plans using the fair value-based method of accounting. The Company recognized total stock based compensation expense of $820 thousand for the three months ended March 31, 2021 and $804 thousand for the three months ended March 31, 2020. Stock Options Options to purchase a total of 1,309,231 shares of Company stock have been granted as of March 31, 2021. Options are exercisable for up to 10 years from the date of the grant and, dependent on the terms of the applicable award agreement generally vest four years after the date of grant. The fair value of stock options granted is estimated at the date of grant using the Black-Scholes option-pricing model. A summary of the activity in the stock option plans during the three months ended March 31, 2021 is set forth below: Weighted Weighted Average Average Aggregate Number of Exercise Remaining Intrinsic Options Price Contractual Term Value (Shares in thousands) (In years) (Dollars in thousands) Options outstanding, January 1, 2021 469 $ 21.08 3.43 $ 6,118 Options granted — — Options exercised (71 ) 18.77 Options forfeited — — Options outstanding, March 31, 2021 398 $ 21.45 3.33 $ 7,573 Options vested and exercisable, March 31, 2021 389 $ 21.01 3.27 $ 7,604 As of March 31, 2021, there was $67 thousand of total unrecognized compensation cost related to nonvested stock options granted under the Plan. The cost is expected to be recognized over a weighted-average period of 0.45 years. Restricted Stock Awards During the three months ended March 31, 2021, the Company issued 67,341 shares of restricted stock. The shares of restricted stock generally vest over a period of four years and are considered outstanding at the date of issuance. The Company accounts for shares of restricted stock by recording the fair value of the grant on the award date as compensation expense over the vesting period. A summary of the activity of the nonvested shares of restricted stock during the three months ended March 31, 2021 is as follows: Weighted Average Grant Number of Date Fair Shares Value (Shares in thousands) Nonvested share awards outstanding, January 1, 2021 158 $ 30.78 Share awards granted 67 38.47 Share awards vested (3 ) 34.85 Unvested share awards forfeited or cancelled (3 ) 37.18 Nonvested share awards outstanding, March 31, 2021 219 $ 33.03 As of March 31, 2021, there was $6.4 million of total unrecognized compensation cost related to the restricted stock awards which is expected to be recognized over a weighted-average period of 2.79 years. Performance Share Units (“PSUs”) PSUs are earned subject to certain performance goals being met after the two-year one-year

OFF-BALANCE SHEET ARRANGEMENTS,

OFF-BALANCE SHEET ARRANGEMENTS, COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
OFF-BALANCE SHEET ARRANGEMENTS, COMMITMENTS AND CONTINGENCIES	14. OFF-BALANCE SHEET ARRANGEMENTS, COMMITMENTS AND CONTINGENCIES In the normal course of business, the Company enters into various transactions, which, in accordance with accounting principles generally accepted in the United States, are not included in the Company’s consolidated balance sheets. The Company enters into these transactions to meet the financing needs of its customers. These transactions include commitments to extend credit and standby letters of credit, which involve to varying degrees elements of credit risk and interest rate risk in excess of the amounts recognized in the consolidated balance sheets. The Company uses the same credit policies in making commitments and conditional obligations as it does for on balance sheet instruments. The contractual amounts of financial instruments with off-balance sheet risk are as follows: March 31, 2021 December 31, 2020 Fixed Variable Fixed Variable Rate Rate Rate Rate (Dollars in thousands) Commitments to extend credit $ 926,569 $ 506,396 $ 761,938 $ 480,067 Standby letters of credit 9,480 7,263 9,252 8,003 Total $ 936,049 $ 513,659 $ 771,190 $ 488,070 Commitments to extend credit include lines of credit as well as commitments to make new loans. Commitments to make loans are generally made for an approval period of 120 days or fewer. As of March 31, 2021, the funded fixed rate loan commitments had interest rates ranging from 1.20% to 13.49% with a weighted average maturity and rate of 3.53 years and 5.07%, respectively. As of December 31, 2020, the funded fixed rate loan commitments had interest rates ranging from 1.20% to 18.00% with a weighted average maturity and rate of 3.53 years and 5.13%, respectively. Litigation From time to time, the Company is subject to claims and litigation arising in the ordinary course of business. In the opinion of management, the Company is not party to any legal proceedings the resolution of which it believes would have a material adverse effect on the Company’s business, prospects, financial condition, liquidity, results of operation, cash flows or capital levels. However, one or more unfavorable outcomes in any claim or litigation against the Company could have a material adverse effect for the period in which such claim or litigation is resolved. In addition, regardless of their merits or their ultimate outcomes, such matters are costly, divert management’s attention and may materially adversely affect the Company’s reputation, even if resolved in its favor. The Company intends to defend itself vigorously against any future claims or litigation.

REGULATORY CAPITAL MATTERS

REGULATORY CAPITAL MATTERS	3 Months Ended
	Mar. 31, 2021
Regulatory Capital Matters [Abstract]
REGULATORY CAPITAL MATTERS	15. REGULATORY CAPITAL MATTERS The Company and the Bank are subject to various regulatory capital requirements administered by the federal banking agencies. Capital adequacy guidelines, and for banks, prompt corrective action regulations, involve quantitative measures of assets, liabilities and certain off balance sheet items calculated under regulatory accounting practices. Capital amounts and classifications are also subject to qualitative judgments by regulators about components, risk weightings and other factors. Failure to meet minimum capital requirements can cause regulators to initiate actions that, if undertaken, could have a direct material effect on the Company’s consolidated financial statements. The final rules implementing Basel Committee on Banking Supervision's capital guideline for U.S. Banks (Basel III Rules) were fully phased in when the capital conservation buffer reached 2.5%. Management believes as of March 31, 2021 and December 31, 2020 the Company and the Bank met all capital adequacy requirements to which they were then subject. Prompt corrective action regulations provide five classifications: well capitalized, adequately capitalized, undercapitalized, significantly undercapitalized, and critically undercapitalized, although these terms are not used to represent overall financial condition. If less than well capitalized, regulatory approval is required to accept brokered deposits. If undercapitalized, capital distributions are limited, as is asset growth and expansion, and capital restoration plans are required. The following is a summary of the Company’s and the Bank’s actual and required capital ratios as of March 31, 2021 and December 31, 2020: Actual Minimum Required for Capital Adequacy Purposes Minimum Required Plus Capital Conservation Buffer To Be Categorized As Well-Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio Amount Ratio (Dollars in thousands) ALLEGIANCE BANCSHARES, INC. (Consolidated) As of March 31, 2021 Total Capital (to risk weighted assets) $ 656,264 15.72 % $ 333,986 8.00 % $ 438,356 10.50 % N/A N/A Common Equity Tier 1 Capital (to risk weighted assets) 495,552 11.87 % 187,867 4.50 % 292,237 7.00 % N/A N/A Tier 1 Capital (to risk weighted assets) 505,218 12.10 % 250,489 6.00 % 354,860 8.50 % N/A N/A Tier 1 Capital (to average tangible assets) 505,218 8.57 % 235,803 4.00 % 235,803 4.00 % N/A N/A As of December 31, 2020 Total Capital (to risk weighted assets) $ 642,155 15.71 % $ 327,084 8.00 % $ 429,298 10.50 % N/A N/A Common Equity Tier 1 Capital (to risk weighted assets) 482,643 11.80 % 183,985 4.50 % 286,199 7.00 % N/A N/A Tier 1 Capital (to risk weighted assets) 492,281 12.04 % 245,313 6.00 % 347,527 8.50 % N/A N/A Tier 1 Capital (to average tangible assets) 492,281 8.51 % 231,518 4.00 % 231,518 4.00 % N/A N/A ALLEGIANCE BANK As of March 31, 2021 Total Capital (to risk weighted assets) $ 641,160 15.37 % $ 333,627 8.00 % $ 437,886 10.50 % $ 417,034 10.00 % Common Equity Tier 1 Capital (to risk weighted assets) 549,178 13.17 % 187,665 4.50 % 291,924 7.00 % 271,072 6.50 % Tier 1 Capital (to risk weighted assets) 549,178 13.17 % 250,221 6.00 % 354,479 8.50 % 333,627 8.00 % Tier 1 Capital (to average tangible assets) 549,178 9.33 % 235,510 4.00 % 235,510 4.00 % 294,387 5.00 % As of December 31, 2020 Total Capital (to risk weighted assets) $ 635,223 15.55 % $ 326,804 8.00 % $ 428,931 10.50 % $ 408,506 10.00 % Common Equity Tier 1 Capital (to risk weighted assets) 544,331 13.32 % 183,828 4.50 % 285,954 7.00 % 265,529 6.50 % Tier 1 Capital (to risk weighted assets) 544,331 13.32 % 245,103 6.00 % 347,230 8.50 % 326,804 8.00 % Tier 1 Capital (to average tangible assets) 544,331 9.41 % 231,334 4.00 % 231,334 4.00 % 289,167 5.00 %

EARNINGS PER COMMON SHARE

EARNINGS PER COMMON SHARE	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
EARNINGS PER COMMON SHARE	16. EARNINGS PER COMMON SHARE Diluted earnings per common share is computed using the weighted-average number of common shares determined for the basic earnings per common share computation plus the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock using the treasury stock method. Outstanding stock options and PSUs issued by the Company represent the only dilutive effect reflected in diluted weighted average shares. Restricted shares are considered outstanding at the date of grant, accounted for as participating securities and included in basic and diluted weighted average common shares outstanding. Performance share units that vest based on the Company’s performance and service conditions that have not been achieved as of the end of the period are not included in basic and diluted weighted average common shares outstanding. Three Months Ended March 31, 2021 2020 Per Share Per Share Amount Amount Amount Amount (Amounts in thousands, except per share data) Net income attributable to shareholders $ 18,010 $ 3,516 Basic: Weighted average shares outstanding 20,140 $ 0.89 20,411 $ 0.17 Diluted: Add incremental shares for: Dilutive effect of stock option exercises 202 279 Total 20,342 $ 0.89 20,690 $ 0.17 There were no antidilutive shares as of March 31, 2021. Stock options for 81,165 shares were not considered in computing diluted earnings per common share as of March 31, 2020 as they were antidilutive.

NATURE OF OPERATIONS AND SUMM_2

NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING AND REPORTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation -The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") for interim financial information and in accordance with guidance provided by the Securities and Exchange Commission. Accordingly, the condensed consolidated financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments considered necessary for a fair presentation of the financial position, results of operations and cash flows of the Company on a consolidated basis, and all such adjustments are of a normal recurring nature. Transactions between the Company and the Bank have been eliminated. The condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020. Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021.
New Accounting Standards	New Accounting Standards Adoption of New Accounting Standards ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU 2019-12”), that removes certain exceptions for investments, intraperiod allocations and interim calculations, and adds guidance to reduce complexity in accounting for income taxes. ASU 2019-12 introduces the following new guidance: i) guidance to evaluate whether a step-up in tax basis of goodwill relates to a business combination in which book goodwill was recognized or a separate transaction and ii) a policy election to not allocate consolidated income taxes when a member of a consolidated tax return is not subject to income tax. Additionally, ASU 2019-12 changes the following current guidance: i) making an intraperiod allocation, if there is a loss in continuing operations and gains outside of continuing operations, ii) determining when a deferred tax liability is recognized after an investor in a foreign entity transitions to or from the equity method of accounting, iii) accounting for tax law changes and year-to-date losses in interim periods, and iv) determining how to apply the income tax guidance to franchise taxes that are partially based on income. The Company adopted ASU 2019-12 on January 1, 2021, which did not have a material impact on the Company’s results of operations, financial position or disclosures. ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASC Topic 326”) , was issued by the FASB in June 2016 along with subsequent amendments thereto, which introduce the current expected credit losses (“CECL”) methodology. The measurement of expected credit losses under the CECL methodology utilizes a lifetime “expected credit loss” measurement objective for the recognition of credit losses for loans, held-to-maturity debt securities measured at amortized cost. ASC Topic 326 also applies to off-balance sheet credit exposures. This methodology replaces the multiple existing impairment methods in current guidance, which generally require that a loss be incurred before it is recognized. Within the life cycle of a loan or other financial asset, this new guidance will generally result in the earlier recognition of the provision for credit losses and the related allowance for credit losses than previous practice. For available for sale debt securities that the Company intends to hold and where fair value is less than cost, credit-related impairment, if any, will be recognized through an allowance for credit losses and adjusted each period for changes in credit risk. CECL became effecti ve for the Company on January 1 ; however, o n March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) was signed in to law by the President of the United States and allowed the option to temporarily defer or suspend the adoption of ASC Topic 326. The Company elected to temporarily defer the adoption of CECL due to the uncertainty of the impact of COVID-19 and the volatility of crude oil prices, which can be impactful to the Houston market. During the deferral, t he Company calculated and recorded its provision for loan losses under the incurred loss model that existed prior to ASC Topic 326. The Company adopted the new standard as of January 1, 2020 , dur ing the fourth quarter of 2020 , using the modified retrospective method such that prior period amounts were not adjusted, but were reported in accordance with p reviously applicable generally accepted accounting principles and a cumulative effect adjustment to the opening balance of retained earnings was recognized . Upon adoption of ASC Topic 326, the Company recognized an increase in allowance for credit losses on loans of $3.1 million and the establishment of an allowance for credit losses for off-balance sheet exposure of $3.9 million and a corresponding decrease in retained earnings of $5.5 million, after-tax. The Company adopted ASC Topic 326 using the prospective transition approach for purchased credit deteriorated (“PCD”) loans, which did not require re-evaluation of whether loans previously classified as purchased credit impaired (“PCI”) loans met the criteria of PCD assets at the date of adoption. The Company recognized an increase in the allowance for credit losses for loans of $2.1 million, due to the reclass of PCD discounts previously classified as PCI with a corresponding adjustment to the gross carrying amount of the loans. The remaining noncredit discount was accreted into interest income at the effective interest rate as of January 1, 2020. See Note 5 “Loans and Allowance for Credit Losses” for additional information. The following table illustrates the impact of adopting ASC Topic 326: As of January 1, 2020 As Reported Under ASC Topic 326 Pre-ASC Topic 326 Adoption Impact of ASC Topic 326 Adoption (Dollars in thousands) Assets: Allowance for credit losses on loans: Commercial and industrial $ 15,840 $ 8,818 $ 7,022 Mortgage warehouse — — — Paycheck Protection Program (PPP) — — — Real estate: Commercial real estate (including multi-family residential) 6,007 11,170 (5,163 ) Commercial real estate construction and land development 6,051 4,421 1,630 1-4 family residential (including home equity) 5,452 3,852 1,600 Residential construction 1,056 1,057 (1 ) Consumer and other 257 120 137 Allowance for credit losses on loans $ 34,663 $ 29,438 $ 5,225 Liabilities: Allowance for credit losses on unfunded commitments $ 3,866 $ — $ 3,866 ASC Topic 326 also requires expected credit losses on available for sale (“AFS”) debt securities to be recorded as an allowance for credit losses. For certain types of debt securities, such as U.S. Treasuries and other securities with government guarantees, entities may expect zero credit losses. The zero-loss expectation generally applies to the Company’s securities and no allowance for credit losses were recorded on its AFS securities portfolio at transition. See Note 4 “Securities” for additional information. Newly Issued But Not Yet Effective Accounting Standards ASU 2020-04, "Reference Rate Reform: Facilitation of the Effects of Reference Rate Reform on Financial Reporting - Accounting Standards Codification (“ASC”) Topic 848." ASU 2020-04 provides optional expedients and exceptions for applying GAAP to loan and lease agreements, derivative contracts, and other transactions affected by the anticipated transition away from LIBOR toward new interest rate benchmarks. The guidance allows for companies to: (i) account for certain contract modifications as a continuation of the existing contract without additional analysis; (ii) continue hedge accounting when certain critical terms of a hedging relationship change and assess effectiveness in ways that disregard certain potential sources of ineffectiveness; and (iii) make a one-time sale and/or transfer of certain debt securities from held-to-maturity to available for sale or trading. This ASU is available for adoption effective March 12, 2020 through December 31, 2022. An entity may elect to apply ASU 2020-04 for contract modifications as of January 1, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. Once elected for a Topic or an Industry Subtopic within ASU 2020-04, the amendments must be applied prospectively for all eligible contract modifications for that Topic or Industry Subtopic. The one-time election to sell and/or transfer debt securities classified as held-to-maturity may be made at any time after March 12, 2020. The Company anticipates this ASU will simplify any modifications it executes between the selected start date (yet to be determined) and December 31, 2022 that are directly related to the LIBOR transition by allowing prospective recognition of the continuation of the contract, rather than extinguishment of the old contract resulting in writing off unamortized fees and costs. ASU 2020-04 is not expected to have a significant impact on the Company’s financial statements.

NATURE OF OPERATIONS AND SUMM_3

NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING AND REPORTING POLICIES (Tables)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Schedule of Impact of Adopting ASC Topic 326	The following table illustrates the impact of adopting ASC Topic 326: As of January 1, 2020 As Reported Under ASC Topic 326 Pre-ASC Topic 326 Adoption Impact of ASC Topic 326 Adoption (Dollars in thousands) Assets: Allowance for credit losses on loans: Commercial and industrial $ 15,840 $ 8,818 $ 7,022 Mortgage warehouse — — — Paycheck Protection Program (PPP) — — — Real estate: Commercial real estate (including multi-family residential) 6,007 11,170 (5,163 ) Commercial real estate construction and land development 6,051 4,421 1,630 1-4 family residential (including home equity) 5,452 3,852 1,600 Residential construction 1,056 1,057 (1 ) Consumer and other 257 120 137 Allowance for credit losses on loans $ 34,663 $ 29,438 $ 5,225 Liabilities: Allowance for credit losses on unfunded commitments $ 3,866 $ — $ 3,866

GOODWILL AND CORE DEPOSIT INT_2

GOODWILL AND CORE DEPOSIT INTANGIBLE ASSETS (Tables)	3 Months Ended
	Mar. 31, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets and Goodwill	Changes in the carrying amount of the Company’s goodwill and core deposit intangible assets were as follows: Core Deposit Goodwill Intangibles (Dollars in thousands) Balance as of December 31, 2019 $ 223,642 $ 21,876 Amortization — (3,922 ) Balance as of December 31, 2020 223,642 17,954 Amortization — (824 ) Balance as of March 31, 2021 $ 223,642 $ 17,130
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The estimated aggregate future amortization expense for core deposit intangible assets remaining as of March 31, 2021 is as follows (dollars in thousands): Remaining 2021 $ 2,472 2022 3,003 2023 2,323 2024 2,188 2025 2,061 Thereafter 5,083 Total $ 17,130

SECURITIES (Tables)

SECURITIES (Tables)	3 Months Ended
	Mar. 31, 2021
Investments Debt And Equity Securities [Abstract]
Available-for-sale Securities	The amortized cost and fair value of investment securities were as follows: March 31, 2021 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value (Dollars in thousands) Available for Sale U.S. government and agency securities $ 24,412 $ 580 $ — $ 24,992 Municipal securities 423,389 25,493 (2,881 ) 446,001 Agency mortgage-backed pass-through securities 172,034 3,204 (1,565 ) 173,673 Agency collateralized mortgage obligations 78,905 3,378 (246 ) 82,037 Corporate bonds and other 58,688 2,187 (62 ) 60,813 Total $ 757,428 $ 34,842 $ (4,754 ) $ 787,516 December 31, 2020 Gross Gross Amortized Unrealized Unrealized Fair Cost Gains Losses Value (Dollars in thousands) Available for Sale U.S. government and agency securities $ 25,545 $ 654 $ — $ 26,199 Municipal securities 392,586 35,079 (60 ) 427,605 Agency mortgage-backed pass-through securities 167,606 3,829 (146 ) 171,289 Agency collateralized mortgage obligations 80,182 4,263 (75 ) 84,370 Corporate bonds and other 62,124 1,352 (49 ) 63,427 Total $ 728,043 $ 45,177 $ (330 ) $ 772,890
Investments Classified by Contractual Maturity Date	The amortized cost and fair value of investment securities at March 31, 2021, by contractual maturity, are shown below. Expected maturities may differ from contractual maturities if borrowers have the right to call or prepay obligations at any time with or without call or prepayment penalties. Amortized Fair Cost Value (Dollars in thousands) Due in one year or less $ 805 $ 807 Due after one year through five years 14,279 14,910 Due after five years through ten years 117,273 121,338 Due after ten years 374,132 394,751 Subtotal 506,489 531,806 Agency mortgage-backed pass through and collateralized mortgage obligation securities 250,939 255,710 Total $ 757,428 $ 787,516
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	Securities with unrealized losses segregated by length of time such securities have been in a continuous loss position are as follows: March 31, 2021 Less than 12 Months More than 12 Months Total Estimated Unrealized Estimated Unrealized Estimated Unrealized Fair Value Losses Fair Value Losses Fair Value Losses (Dollars in thousands) Available for Sale Municipal securities $ 88,124 $ (2,881 ) $ — $ — $ 88,124 $ (2,881 ) Agency mortgage-backed pass-through securities 92,920 (1,565 ) — — 92,920 (1,565 ) Agency collateralized mortgage obligations 11,842 (212 ) 4,074 (34 ) 15,916 (246 ) Corporate bonds and other 6,841 (62 ) — — 6,841 (62 ) Total $ 199,727 $ (4,720 ) $ 4,074 $ (34 ) $ 203,801 $ (4,754 ) December 31, 2020 Less than 12 Months More than 12 Months Total Estimated Unrealized Estimated Unrealized Estimated Unrealized Fair Value Losses Fair Value Losses Fair Value Losses (Dollars in thousands) Available for Sale Municipal securities $ 8,844 $ (60 ) $ — $ — $ 8,844 $ (60 ) Agency mortgage-backed pass-through securities 28,659 (146 ) — — 28,659 (146 ) Agency collateralized mortgage obligations 11,629 (39 ) 4,203 (36 ) 15,832 (75 ) Corporate bonds and other 15,951 (49 ) — — 15,951 (49 ) Total $ 65,083 $ (294 ) $ 4,203 $ (36 ) $ 69,286 $ (330 )

LOANS AND ALLOWANCE FOR CREDI_2

LOANS AND ALLOWANCE FOR CREDIT LOSSES (Tables)	3 Months Ended
	Mar. 31, 2021
Loans And Allowance For Credit Losses [Abstract]
Schedule of Accounts, Notes, Loans and Financing Receivable	The loan portfolio balances, net of unearned income and fees, consist of various types of loans primarily made to borrowers located within Texas and are classified by major type as follows: March 31, 2021 December 31, 2020 (Dollars in thousands) Commercial and industrial $ 664,792 $ 667,079 Paycheck Protection Program (PPP) 728,424 569,901 Real estate: Commercial real estate (including multi-family residential) 2,018,853 1,999,877 Commercial real estate construction and land development 386,637 367,213 1-4 family residential (including home equity) 726,228 737,605 Residential construction 119,528 127,522 Consumer and other 14,707 22,567 Total loans 4,659,169 4,491,764 Allowance for credit losses on loans (52,758 ) (53,173 ) Loans, net $ 4,606,411 $ 4,438,591
Past Due Financing Receivables	An aging analysis of the recorded investment in past due loans, segregated by class of loans, is included below. For purposes of this and future disclosures recorded investment has been defined as the outstanding loan balances including net deferred loan fees, and excluding accrued interest receivable of $33.5 million and $34.5 million as of March 31, 2021 and December 31, 2020, respectively, due to immateriality. March 31, 2021 Loans Past Due and Still Accruing 30-89 90 or More Total Past Nonaccrual Current Total Days Days Due Loans Loans Loans Loans (Dollars in thousands) Commercial and industrial $ 3,941 $ — $ 3,941 $ 14,059 $ 646,792 $ 664,792 Paycheck Protection Program (PPP) — — — — 728,424 728,424 Real estate: Commercial real estate (including multi-family residential) 8,712 — 8,712 13,455 1,996,686 2,018,853 Commercial real estate construction and land development 5,691 — 5,691 1,000 379,946 386,637 1-4 family residential (including home equity) 2,488 — 2,488 5,736 718,004 726,228 Residential construction 324 — 324 — 119,204 119,528 Consumer and other 6 — 6 801 13,900 14,707 Total loans $ 21,162 $ — $ 21,162 $ 35,051 $ 4,602,956 $ 4,659,169 December 31, 2020 Loans Past Due and Still Accruing 30-89 90 or More Total Past Nonaccrual Current Total Days Days Due Loans Loans Loans Loans (Dollars in thousands) Commercial and industrial $ 2,486 $ — $ 2,486 $ 10,747 $ 653,846 $ 667,079 Paycheck Protection Program (PPP) — — — — 569,901 569,901 Real estate: Commercial real estate (including multi-family residential) 3,063 — 3,063 10,081 1,986,733 1,999,877 Commercial real estate construction and land development 2,930 — 2,930 3,011 361,272 367,213 1-4 family residential (including home equity) 3,000 — 3,000 4,525 730,080 737,605 Residential construction — — — — 127,522 127,522 Consumer and other 46 — 46 529 21,992 22,567 Total loans $ 11,525 $ — $ 11,525 $ 28,893 $ 4,451,346 $ 4,491,764
Impaired Financing Receivables	The following table presents risk ratings by category of loan as of March 31, 2021 and December 31, 2020: As of March 31, 2021 As of December 31, 2020 Term Loans Amortized Cost Basis by Origination Year 2021 2020 2019 2018 2017 Prior Revolving Loans Revolving Loans Converted to Term Loans Total Total (Dollars in thousands) Commercial and industrial Pass $ 42,316 $ 130,986 $ 74,052 $ 45,122 $ 17,573 $ 25,166 $ 235,233 $ — $ 570,448 $ 562,518 Watch 4,886 8,079 5,314 4,381 1,198 1,839 15,629 — 41,326 41,026 Special Mention 784 1,151 2,663 1,798 1,105 2,487 6,148 — 16,136 25,010 Substandard 4,629 11,859 3,007 3,157 4,829 1,245 7,932 — 36,658 38,385 Doubtful — 213 — 11 — — — — 224 140 Total commercial and industrial loans $ 52,615 $ 152,288 $ 85,036 $ 54,469 $ 24,705 $ 30,737 $ 264,942 $ — $ 664,792 $ 667,079 Paycheck Protection Program (PPP) Pass $ 331,736 $ 396,538 $ — $ — $ — $ 150 $ — $ — $ 728,424 $ 569,901 Watch — — — — — — — — — — Special Mention — — — — — — — — — — Substandard — — — — — — — — — — Doubtful — — — — — — — — — — Total PPP loans $ 331,736 $ 396,538 $ — $ — $ — $ 150 $ — $ — $ 728,424 $ 569,901 Commercial real estate (including multi-family residential) Pass $ 153,677 $ 586,634 $ 296,323 $ 200,738 $ 190,080 $ 212,707 $ 47,193 $ — $ 1,687,352 $ 1,629,023 Watch 6,612 25,111 39,322 17,722 23,039 36,873 1,956 — 150,635 177,651 Special Mention 6,115 11,053 8,007 6,003 10,328 14,462 647 — 56,615 68,276 Substandard 2,909 21,312 24,711 17,806 23,616 31,344 2,553 — 124,251 124,927 Doubtful — — — — — — — — — — Total commercial real estate (including multi-family residential) loans $ 169,313 $ 644,110 $ 368,363 $ 242,269 $ 247,063 $ 295,386 $ 52,349 $ — $ 2,018,853 $ 1,999,877 Commercial real estate construction and land development Pass $ 39,047 $ 171,318 $ 61,948 $ 29,238 $ 13,064 $ 8,001 $ 14,375 $ — $ 336,991 $ 320,133 Watch 1,214 17,351 3,466 3,253 6,332 2,606 — — 34,222 39,021 Special Mention 523 2,091 2,967 374 911 261 113 — 7,240 2,880 Substandard — 5,983 966 680 — — 555 — 8,184 5,179 Doubtful — — — — — — — — — — Total commercial real estate construction and land development $ 40,784 $ 196,743 $ 69,347 $ 33,545 $ 20,307 $ 10,868 $ 15,043 $ — $ 386,637 $ 367,213 1-4 family residential (including home equity) Pass $ 55,339 $ 199,484 $ 111,305 $ 89,416 $ 60,582 $ 61,211 $ 84,886 $ — $ 662,223 $ 670,074 Watch 3,108 11,833 3,110 4,135 5,660 4,300 4,455 — 36,601 37,667 Special Mention — 2,387 1,472 4,284 390 4,757 2,453 — 15,743 18,790 Substandard — 1,375 2,527 3,073 1,499 2,969 218 — 11,661 11,074 Doubtful — — — — — — — — — — Total 1-4 family residential (including home equity) $ 58,447 $ 215,079 $ 118,414 $ 100,908 $ 68,131 $ 73,237 $ 92,012 $ — $ 726,228 $ 737,605 As of March 31, 2021 As of December 31, 2020 Term Loans Amortized Cost Basis by Origination Year 2021 2020 2019 2018 2017 Prior Revolving Loans Revolving Loans Converted to Term Loans Total Total (Dollars in thousands) Residential construction Pass $ 16,204 $ 85,597 $ 6,971 $ 5,266 $ 730 $ 730 $ — $ — $ 115,498 $ 124,737 Watch 50 2,584 742 — — — — — 3,376 2,785 Special Mention — 654 — — — — — — 654 — Substandard — — — — — — — — — — Doubtful — — — — — — — — — — Total residential construction $ 16,254 $ 88,835 $ 7,713 $ 5,266 $ 730 $ 730 $ — $ — $ 119,528 $ 127,522 Consumer and other Pass (1) $ (11,511 ) $ 16,325 $ 2,469 $ 1,360 $ 485 $ 130 $ 4,027 $ — $ 13,285 $ 21,359 Watch — 53 161 3 — — 63 — 280 389 Special Mention — 224 — 33 — — 3 — 260 270 Substandard — 470 300 39 73 — — — 882 549 Doubtful — — — — — — — — — — Total consumer and other $ (11,511 ) $ 17,072 $ 2,930 $ 1,435 $ 558 $ 130 $ 4,093 $ — $ 14,707 $ 22,567 Total loans Pass $ 626,808 $ 1,586,882 $ 553,068 $ 371,140 $ 282,514 $ 308,095 $ 385,714 $ — $ 4,114,221 $ 3,897,745 Watch 15,870 65,011 52,115 29,494 36,229 45,618 22,103 — 266,440 298,539 Special Mention 7,422 17,560 15,109 12,492 12,734 21,967 9,364 — 96,648 115,226 Substandard 7,538 40,999 31,511 24,755 30,017 35,558 11,258 — 181,636 180,114 Doubtful — 213 — 11 — — — — 224 140 Total loans $ 657,638 $ 1,710,665 $ 651,803 $ 437,892 $ 361,494 $ 411,238 $ 428,439 $ — $ 4,659,169 $ 4,491,764 (1) Includes net deferred fees of $22.0 million and $13.9 million on PPP loans as of March 31, 2021 and December 31, 2020, respectively.
Allowance for Credit Losses on Financing Receivables	The following table presents the activity in the allowance for credit losses on loans by portfolio type for the three months ended March 31, 2021 and 2020: Commercial and Paycheck Protection Program (PPP) Commercial real estate (including multi-family residential) Commercial real estate construction and land development 1-4 family residential (including home equity) Residential construction Consumer and other Total (Dollars in thousands) Allowance for credit losses on loans: Three Months Ended Balance December 31, 2020 $ 17,738 $ — $ 23,934 $ 6,939 $ 3,279 $ 870 $ 413 $ 53,173 Provision for loan losses 1,304 — (155 ) 683 (1,723 ) (45 ) (134 ) (70 ) Charge-offs (404 ) — — — — — — (404 ) Recoveries 59 — — — — — — 59 Net charge-offs (345 ) — — — — — — (345 ) Balance March 31, 2021 $ 18,697 $ — $ 23,779 $ 7,622 $ 1,556 $ 825 $ 279 $ 52,758 Allowance for loan losses: Three Months Ended Balance December 31, 2019 $ 8,818 $ — $ 11,170 $ 4,421 $ 3,852 $ 1,057 $ 120 $ 29,438 Provision for loan losses 1,865 — 5,725 732 2,296 374 (2 ) 10,990 Charge-offs (734 ) — (144 ) (2,164 ) (90 ) — — (3,132 ) Recoveries 215 — — — — — — 215 Net charge-offs (519 ) — (144 ) (2,164 ) (90 ) — — (2,917 ) Balance March 31, 2020 $ 10,164 $ — $ 16,751 $ 2,989 $ 6,058 $ 1,431 $ 118 $ 37,511
Summary of Activity in Allowance for Credit Losses on Unfunded Commitments	The following table details activity in the allowance for credit losses on unfunded commitments as of March 31, 2021 is as follows (dollars in thousands): Balance at December 31, 2020 $ 4,697 Provision for credit losses on unfunded commitments 709 Balance at March 31, 2021 $ 5,406
Summary of Amortized Cost Basis of Collateral Dependent Loans Individually Evaluated to Determine Expected Credit Losses	. The following table presents the amortized cost basis of collateral dependent loans, which are individually evaluated to determine expected credit losses as of March 31, 2021 and December 31, 2020: As of March 31, 2021 Real Estate Business Assets Other Total (Dollars in thousands) Commercial and industrial $ — $ 8,619 $ — $ 8,619 Paycheck Protection Program (PPP) — — — — Real estate: Commercial real estate (including multi-family residential) 707 — — 707 Commercial real estate construction and land development 1,000 — — 1,000 1-4 family residential (including home equity) 5,572 — — 5,572 Residential construction — — — — Consumer and other — — 280 280 Total $ 7,279 $ 8,619 $ 280 $ 16,178 As of December 31, 2020 Real Estate Business Assets Other Total (Dollars in thousands) Commercial and industrial $ — $ 5,157 $ — $ 5,157 Paycheck Protection Program (PPP) — — — — Real estate: Commercial real estate (including multi-family residential) 425 — — 425 Commercial real estate construction and land development — — — — 1-4 family residential (including home equity) 3,101 — — 3,101 Residential construction — — — — Consumer and other — — — — Total $ 3,526 $ 5,157 $ — $ 8,683
Summary of Nonaccrual Loans	The following table presents additional information regarding nonaccrual loans. No interest income was recognized on nonaccrual loans as of March 31, 2021 and December 31, 2020. As of March 31, 2021 Nonaccrual Loans with No Related Allowance Nonaccrual Loans with Related Allowance Total Nonaccrual Loans (Dollars in thousands) Commercial and industrial $ 2,906 $ 11,153 $ 14,059 Paycheck Protection Program (PPP) — — — Real estate: Commercial real estate (including multi-family residential) 4,191 9,264 13,455 Commercial real estate construction and land development 1,000 — 1,000 1-4 family residential (including home equity) 5,160 576 5,736 Residential construction — — — Consumer and other 625 176 801 Total loans $ 13,882 $ 21,169 $ 35,051 As of December 31, 2020 Nonaccrual Loans with No Related Allowance Nonaccrual Loans with Related Allowance Total Nonaccrual Loans (Dollars in thousands) Commercial and industrial $ 2,097 $ 8,650 $ 10,747 Paycheck Protection Program (PPP) — — — Real estate: Commercial real estate (including multi-family residential) 7,487 2,594 10,081 Commercial real estate construction and land development 2,958 53 3,011 1-4 family residential (including home equity) 2,652 1,873 4,525 Residential construction — — — Consumer and other — 529 529 Total loans $ 15,194 $ 13,699 $ 28,893
Troubled Debt Restructurings on Financing Receivables	The following table presents information regarding loans modified in a troubled debt restructuring during the three months ended March 31, 2021 and 2020: Three Months Ended March 31, 2021 2020 Number of Contracts Pre-Modification of Outstanding Recorded Investment Post Modification of Outstanding Recorded Investment Number of Contracts Pre-Modification of Outstanding Recorded Investment Post Modification of Outstanding Recorded Investment (Dollars in thousands) Troubled Debt Restructurings Commercial and industrial — $ — $ — 5 $ 1,104 $ 1,104 Paycheck Protection Program (PPP) — — — — — — Real estate: Commercial real estate (including multi-family residential) 1 545 545 — — — Commercial real estate construction and land development — — — — — — 1-4 family residential (including home equity) — — — 1 118 118 Residential construction — — — — — — Consumer and other — — — 1 30 30 Total 1 $ 545 $ 545 7 $ 1,252 $ 1,252
Schedule of Principal and Interest Deferrals Associated with Loan Modifications Related to COVID 19	The following table presents information regarding principal and interest deferrals as of March 31, 2021 associated with loan modifications related to COVID-19: Initial Deferrals Additional Deferrals Remaining Deferrals Outstanding Loan Balance Deferred Loan Balance Percentage of Total Deferrals Deferred Loan Balance Percentage of Total Deferrals Deferred Loan Balance Percentage of Total Deferrals (Dollars in thousands) Commercial and industrial $ 664,792 $ 109,866 10.3 % $ 22,134 9.3 % $ 6,398 10.3 % Paycheck Protection Program (PPP) 728,424 — 0.0 % — 0.0 % — 0.0 % Real estate: Commercial real estate (including multi-family residential) 2,018,853 761,179 71.5 % 182,662 76.8 % 48,646 78.3 % Commercial real estate construction and land development 386,637 81,566 7.7 % 19,991 8.4 % 2,613 4.2 % 1-4 family residential (including home equity) 726,228 108,870 10.2 % 12,700 5.3 % 4,463 7.2 % Residential construction 119,528 1,687 0.2 % 161 0.1 % — 0.0 % Consumer and other 14,707 805 0.1 % 157 0.1 % — 0.0 % Total loans $ 4,659,169 $ 1,063,973 100.0 % $ 237,805 100.0 % $ 62,120 100.0 %

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Supplemental Lease Information	Supplemental lease information at the dates indicated is as follows: March 31, 2021 December 31, 2020 (Dollars in thousands) Balance Sheet: Operating lease right of use asset classified as premises and equipment $ 11,399 $ 11,610 Operating lease liability classified as other liabilities $ 11,625 $ 11,850 Weighted average lease term, in years 5.40 5.56 Weighted average discount rate 2.77 % 2.86 %
Summary of Lease Costs	Lease costs for the dates indicated is as follows: Three Months Ended March 31, 2021 2020 (Dollars in thousands) Income Statement: Operating lease cost $ 873 $ 799 Short-term lease cost 15 36 Sublease income (18 ) (18 ) Total operating lease costs $ 870 $ 817
Maturity Analysis of Lease Liabilities	A maturity analysis of the Company’s lease liabilities is as follows: March 31, 2021 December 31, 2020 (Dollars in thousands) Lease payments due: Within one year $ 3,132 $ 3,068 After one but within two years 2,539 2,664 After two but within three years 2,120 2,056 After three but within four years 1,490 1,591 After four but within five years 1,069 1,057 After five years 2,144 2,355 Total lease payments 12,494 12,791 Discount on cash flows 869 941 Total lease liability $ 11,625 $ 11,850

FAIR VALUE (Tables)

FAIR VALUE (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value, by Balance Sheet Grouping	The carrying amounts and estimated fair values of financial instruments that are reported on the balance sheet are as follows: As of March 31, 2021 Carrying Estimated Fair Value Amount Level 1 Level 2 Level 3 Total (Dollars in thousands) Financial assets Cash and cash equivalents $ 624,330 $ 624,330 $ — $ — $ 624,330 Available for sale securities 787,516 — 787,516 — 787,516 Loans held for investment, net of allowance 4,606,411 — — 4,605,252 4,605,252 Interest rate swap 572 — 572 — 572 Accrued interest receivable 38,632 3 5,133 33,496 38,632 Financial liabilities Deposits $ 5,374,189 $ — $ 5,383,876 $ — $ 5,383,876 Accrued interest payable 3,862 — 3,862 — 3,862 Borrowed funds 147,517 — 132,123 — 132,123 Subordinated debt 108,453 — 109,935 — 109,935 As of December 31, 2020 Carrying Estimated Fair Value Amount Level 1 Level 2 Level 3 Total (Dollars in thousands) Financial assets Cash and cash equivalents $ 422,766 $ 422,766 $ — $ — $ 422,766 Available for sale securities 772,890 — 772,890 — 772,890 Loans held for investment, net of allowance 4,438,591 — — 4,431,816 4,431,816 Accrued interest receivable 40,053 2 5,531 34,520 40,053 Financial liabilities Deposits $ 4,988,482 $ — $ 5,003,594 $ — $ 5,003,594 Interest rate swap 1,252 — 1,252 — 1,252 Accrued interest payable 2,701 — 2,701 — 2,701 Borrowed funds 155,515 — 144,629 — 144,629 Subordinated debt 108,322 — 109,832 — 109,832
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables present fair values for assets and liabilities measured at fair value on a recurring basis. There were no liabilities measured at fair value on a recurring basis as of March 31, 2021. March 31, 2021 Level 1 Level 2 Level 3 Total (Dollars in thousands) Financial assets Available for sale securities: U.S. government and agency securities $ — $ 24,992 $ — $ 24,992 Municipal securities — 446,001 — 446,001 Agency mortgage-backed pass-through securities — 173,673 — 173,673 Agency collateralized mortgage obligations — 82,037 — 82,037 Corporate bonds and other — 60,813 — 60,813 Total available for sale securities $ — $ 787,516 $ — $ 787,516 Interest rate swap $ — $ 572 $ — $ 572 December 31, 2020 Level 1 Level 2 Level 3 Total (Dollars in thousands) Financial assets Available for sale securities: U.S. government and agency securities $ — $ 26,199 $ — $ 26,199 Municipal securities — 427,605 — 427,605 Agency mortgage-backed pass-through securities — 171,289 — 171,289 Agency collateralized mortgage obligations — 84,370 — 84,370 Corporate bonds and other — 63,427 — 63,427 Total available for sale securities $ — $ 772,890 $ — $ 772,890 Financial liabilities Interest rate swap $ — $ 1,252 $ — $ 1,252
Fair Value Measurements, Nonrecurring	Assets measured at fair value on a nonrecurring basis are summarized in the table below. There were no liabilities measured at fair value on a nonrecurring basis at March 31, 2021 and December 31, 2020. As of March 31, 2021 Level 1 Level 2 Level 3 (Dollars in thousands) Collateral Dependent Loans: Commercial and industrial $ — $ — $ 11,153 Commercial real estate (including multi- family residential) — — 9,264 Commercial real estate construction and land development — — — 1-4 family residential (including home equity) — — 576 Residential construction — — — Consumer and other — — 176 Other real estate owned — — 576 $ — $ — $ 21,745 As of December 31, 2020 Level 1 Level 2 Level 3 (Dollars in thousands) Collateral Dependent Loans: Commercial and industrial $ — $ — $ 8,650 Commercial real estate (including multi- family residential) — — 2,594 Commercial real estate construction and land development — — 53 1-4 family residential (including home equity) — — 1,873 Residential construction — — — Consumer and other — — 529 Other real estate owned — — 9,196 $ — $ — $ 22,895

DEPOSITS (Tables)

DEPOSITS (Tables)	3 Months Ended
	Mar. 31, 2021
Deposit Liabilities [Abstract]
Schedule of Maturities of Time Deposits	Scheduled maturities of time deposits for the next five years are as follows (dollars in thousands): Within one year $ 868,760 After one but within two years 367,037 After two but within three years 68,547 After three but within four years 28,664 After four but within five years 28,527 Total $ 1,361,535

DERIVATIVE INSTRUMENTS (Tables)

DERIVATIVE INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2021
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Summary of Cash Flow Hedge Relationships	A summary of the Company’s cash flow hedge relationship as of March 31, 2021 is as follows: Balance Sheet Location Weighted Average Maturity (In Years) Weighted Average Pay Rate Receive Rate Notional Amount Estimated Fair Value (Dollars in thousands) Liability derivatives Interest rate swaps Other assets 4.02 0.64% 3 month LIBOR $ 100,000 $ 572
Effect of Cash Flow Hedge Relationship on Statement of Comprehensive Income	The effects of the Company’s cash flow hedge relationship on the statement of comprehensive income during the three months ended March Amount of Loss Recognized in Other Comprehensive Income Three Months Ended March 31, 2021 2020 (Dollars in thousands) Liability derivatives Interest rate swaps $ 1,824 $ —

SUBORDINATED DEBT (Tables)

SUBORDINATED DEBT (Tables)	3 Months Ended
	Mar. 31, 2021
Subordinated Borrowings [Abstract]
Schedule of Subordinated Borrowing	A summary of pertinent information related to the Company’s issues of junior subordinated debentures outstanding at March 31, 2021 is set forth in the table below: Description Issuance Date Trust Preferred Securities Outstanding Interest Rate (1) Junior Subordinated Debt Owed to Trusts Maturity Date (2) (Dollars in thousands) Farmers & Merchants Capital Trust II November 13, 2003 $ 7,500 3 month LIBOR + 3.00% $ 7,732 November 8, 2033 Farmers & Merchants Capital Trust III June 30, 2005 3,500 3 month LIBOR + 1.80% 3,609 July 7, 2035 $ 11,341 (1) The 3-month LIBOR in effect as of March 31, 2021 was 0.18962%. (2) All debentures are currently callable.

STOCK BASED COMPENSATION (Table

STOCK BASED COMPENSATION (Tables)	9 Months Ended
	Sep. 30, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Schedule of Share-based Compensation, Stock Options, Activity	A summary of the activity in the stock option plans during the three months ended March 31, 2021 is set forth below: Weighted Weighted Average Average Aggregate Number of Exercise Remaining Intrinsic Options Price Contractual Term Value (Shares in thousands) (In years) (Dollars in thousands) Options outstanding, January 1, 2021 469 $ 21.08 3.43 $ 6,118 Options granted — — Options exercised (71 ) 18.77 Options forfeited — — Options outstanding, March 31, 2021 398 $ 21.45 3.33 $ 7,573 Options vested and exercisable, March 31, 2021 389 $ 21.01 3.27 $ 7,604
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	A summary of the activity of the nonvested shares of restricted stock during the three months ended March 31, 2021 is as follows: Weighted Average Grant Number of Date Fair Shares Value (Shares in thousands) Nonvested share awards outstanding, January 1, 2021 158 $ 30.78 Share awards granted 67 38.47 Share awards vested (3 ) 34.85 Unvested share awards forfeited or cancelled (3 ) 37.18 Nonvested share awards outstanding, March 31, 2021 219 $ 33.03

OFF-BALANCE SHEET ARRANGEMENT_2

OFF-BALANCE SHEET ARRANGEMENTS, COMMITMENTS AND CONTINGENCIES (Tables)	3 Months Ended
	Mar. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Schedule of Fair Value, Off-balance Sheet Risks	The contractual amounts of financial instruments with off-balance sheet risk are as follows: March 31, 2021 December 31, 2020 Fixed Variable Fixed Variable Rate Rate Rate Rate (Dollars in thousands) Commitments to extend credit $ 926,569 $ 506,396 $ 761,938 $ 480,067 Standby letters of credit 9,480 7,263 9,252 8,003 Total $ 936,049 $ 513,659 $ 771,190 $ 488,070

REGULATORY CAPITAL MATTERS (Tab

REGULATORY CAPITAL MATTERS (Tables)	3 Months Ended
	Mar. 31, 2021
Regulatory Capital Matters [Abstract]
Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations	The following is a summary of the Company’s and the Bank’s actual and required capital ratios as of March 31, 2021 and December 31, 2020: Actual Minimum Required for Capital Adequacy Purposes Minimum Required Plus Capital Conservation Buffer To Be Categorized As Well-Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio Amount Ratio (Dollars in thousands) ALLEGIANCE BANCSHARES, INC. (Consolidated) As of March 31, 2021 Total Capital (to risk weighted assets) $ 656,264 15.72 % $ 333,986 8.00 % $ 438,356 10.50 % N/A N/A Common Equity Tier 1 Capital (to risk weighted assets) 495,552 11.87 % 187,867 4.50 % 292,237 7.00 % N/A N/A Tier 1 Capital (to risk weighted assets) 505,218 12.10 % 250,489 6.00 % 354,860 8.50 % N/A N/A Tier 1 Capital (to average tangible assets) 505,218 8.57 % 235,803 4.00 % 235,803 4.00 % N/A N/A As of December 31, 2020 Total Capital (to risk weighted assets) $ 642,155 15.71 % $ 327,084 8.00 % $ 429,298 10.50 % N/A N/A Common Equity Tier 1 Capital (to risk weighted assets) 482,643 11.80 % 183,985 4.50 % 286,199 7.00 % N/A N/A Tier 1 Capital (to risk weighted assets) 492,281 12.04 % 245,313 6.00 % 347,527 8.50 % N/A N/A Tier 1 Capital (to average tangible assets) 492,281 8.51 % 231,518 4.00 % 231,518 4.00 % N/A N/A ALLEGIANCE BANK As of March 31, 2021 Total Capital (to risk weighted assets) $ 641,160 15.37 % $ 333,627 8.00 % $ 437,886 10.50 % $ 417,034 10.00 % Common Equity Tier 1 Capital (to risk weighted assets) 549,178 13.17 % 187,665 4.50 % 291,924 7.00 % 271,072 6.50 % Tier 1 Capital (to risk weighted assets) 549,178 13.17 % 250,221 6.00 % 354,479 8.50 % 333,627 8.00 % Tier 1 Capital (to average tangible assets) 549,178 9.33 % 235,510 4.00 % 235,510 4.00 % 294,387 5.00 % As of December 31, 2020 Total Capital (to risk weighted assets) $ 635,223 15.55 % $ 326,804 8.00 % $ 428,931 10.50 % $ 408,506 10.00 % Common Equity Tier 1 Capital (to risk weighted assets) 544,331 13.32 % 183,828 4.50 % 285,954 7.00 % 265,529 6.50 % Tier 1 Capital (to risk weighted assets) 544,331 13.32 % 245,103 6.00 % 347,230 8.50 % 326,804 8.00 % Tier 1 Capital (to average tangible assets) 544,331 9.41 % 231,334 4.00 % 231,334 4.00 % 289,167 5.00 %

EARNINGS PER COMMON SHARE (Tabl

EARNINGS PER COMMON SHARE (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Restricted shares are considered outstanding at the date of grant, accounted for as participating securities and included in basic and diluted weighted average common shares outstanding. Performance share units that vest based on the Company’s performance and service conditions that have not been achieved as of the end of the period are not included in basic and diluted weighted average common shares outstanding. Three Months Ended March 31, 2021 2020 Per Share Per Share Amount Amount Amount Amount (Amounts in thousands, except per share data) Net income attributable to shareholders $ 18,010 $ 3,516 Basic: Weighted average shares outstanding 20,140 $ 0.89 20,411 $ 0.17 Diluted: Add incremental shares for: Dilutive effect of stock option exercises 202 279 Total 20,342 $ 0.89 20,690 $ 0.17

NATURE OF OPERATIONS AND SUMM_4

NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING AND REPORTING POLICIES (Details) $ in Thousands	Jan. 01, 2020USD ($)	Mar. 31, 2021USD ($)officeBank	Dec. 31, 2020USD ($)
New Accounting Pronouncement Early Adoption [Line Items]
Number of offices in which entity operates | office		27
Retained earnings		$ 210,834	$ 195,236
Accounting Standards Update 2016-13
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans	$ 3,100
Off-balance sheet exposure for allowance for credit losses	3,900
Increase in allowance for credit losses for loans	2,100
Accounting Standards Update 2016-13 | Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncement Early Adoption [Line Items]
Retained earnings	$ (5,500)
Houston
New Accounting Pronouncement Early Adoption [Line Items]
Number of banks in which entity operates | Bank		26
Beaumont
New Accounting Pronouncement Early Adoption [Line Items]
Number of banks in which entity operates | Bank		1

NATURE OF OPERATIONS AND SUMM_5

NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING AND REPORTING POLICIES - Schedule of Impact of Adopting ASC Topic 326 (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans	$ 52,758	$ 53,173	$ 37,511	$ 34,663	$ 29,438
Liabilities:
Allowance for credit losses on unfunded commitments				3,866
Impact of ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				5,225
Liabilities:
Allowance for credit losses on unfunded commitments				3,866
Pre-ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				29,438
Commercial and industrial
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				15,840
Commercial and industrial | Impact of ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				7,022
Commercial and industrial | Pre-ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				8,818
Commercial real estate (including multi-family residential)
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				6,007
Commercial real estate (including multi-family residential) | Impact of ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				(5,163)
Commercial real estate (including multi-family residential) | Pre-ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				11,170
Commercial real estate construction and land development
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				6,051
Commercial real estate construction and land development | Impact of ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				1,630
Commercial real estate construction and land development | Pre-ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				4,421
1-4 family residential (including home equity)
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				5,452
1-4 family residential (including home equity) | Impact of ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				1,600
1-4 family residential (including home equity) | Pre-ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				3,852
Residential construction
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				1,056
Residential construction | Impact of ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				(1)
Residential construction | Pre-ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				1,057
Consumer and other
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				257
Consumer and other | Impact of ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				137
Consumer and other | Pre-ASC Topic 326 Adoption
New Accounting Pronouncement Early Adoption [Line Items]
Allowance for credit losses on loans				$ 120

GOODWILL AND CORE DEPOSIT INT_3

GOODWILL AND CORE DEPOSIT INTANGIBLE ASSETS - Changes in Carrying Amount of Goodwill and Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Goodwill
Balance, beginning	$ 223,642	$ 223,642	$ 223,642
Balance, ending	223,642		223,642
Core Deposit Intangible Assets
Balance, beginning	17,954
Amortization	(824)	(990)
Balance, ending	17,130		17,954
Core Deposit Intangible Assets
Core Deposit Intangible Assets
Balance, beginning	17,954	$ 21,876	21,876
Amortization	(824)		(3,922)
Balance, ending	$ 17,130		$ 17,954

GOODWILL AND CORE DEPOSIT INT_4

GOODWILL AND CORE DEPOSIT INTANGIBLE ASSETS - Narrative (Details)	3 Months Ended
	Mar. 31, 2021USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and other intangible assets impairment	$ 0

GOODWILL AND CORE DEPOSIT INT_5

GOODWILL AND CORE DEPOSIT INTANGIBLE ASSETS - Estimated Aggregate Future Amortization Expense for Core Deposit Intangibles (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Remaining 2021	$ 2,472
2022	3,003
2023	2,323
2024	2,188
2025	2,061
Thereafter	5,083
Total	$ 17,130	$ 17,954

SECURITIES - Amortized Cost and

SECURITIES - Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 757,428	$ 728,043
Gross Unrealized Gains	34,842	45,177
Gross Unrealized Losses	(4,754)	(330)
Fair Value	787,516	772,890
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	24,412	25,545
Gross Unrealized Gains	580	654
Fair Value	24,992	26,199
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	423,389	392,586
Gross Unrealized Gains	25,493	35,079
Gross Unrealized Losses	(2,881)	(60)
Fair Value	446,001	427,605
Agency mortgage-backed pass-through securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	172,034	167,606
Gross Unrealized Gains	3,204	3,829
Gross Unrealized Losses	(1,565)	(146)
Fair Value	173,673	171,289
Agency collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	78,905	80,182
Gross Unrealized Gains	3,378	4,263
Gross Unrealized Losses	(246)	(75)
Fair Value	82,037	84,370
Corporate bonds and other
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	58,688	62,124
Gross Unrealized Gains	2,187	1,352
Gross Unrealized Losses	(62)	(49)
Fair Value	$ 60,813	$ 63,427

SECURITIES - Narrative (Details

SECURITIES - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Investments Debt And Equity Securities [Abstract]
Allowance for credit losses for available for sale securities	$ 0
Gross realized gains	49,000	$ 298,000
Gross realized losses		104,000
Net realized gain (loss)		194,000
Proceeds from sales of available for sale securities	4,900,000	$ 29,700,000
Security owned and pledged as collateral	$ 18,500,000		$ 18,500,000

SECURITIES - Amortized Cost a_2

SECURITIES - Amortized Cost and Fair Value of Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Amortized Cost
Due in one year or less	$ 805
Due after one year through five years	14,279
Due after five years through ten years	117,273
Due after ten years	374,132
Subtotal	506,489
Agency mortgage-backed pass through and collateralized mortgage obligation securities	250,939
Amortized Cost	757,428	$ 728,043
Fair Value
Due in one year or less	807
Due after one year through five years	14,910
Due after five years through ten years	121,338
Due after ten years	394,751
Subtotal	531,806
Agency mortgage-backed pass through and collateralized mortgage obligation securities	255,710
Total	$ 787,516	$ 772,890

SECURITIES - Securities in a Co

SECURITIES - Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Securities in a Continuous Unrealized Loss Position, Less than 12 months, Estimated Fair Value	$ 199,727	$ 65,083
Securities in a Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(4,720)	(294)
Securities in a Continuous Unrealized Loss Position, More than 12 Months, Estimated Fair Value	4,074	4,203
Securities in a Continuous Unrealized Loss Position, More than 12 Months Unrealized Losses	(34)	(36)
Securities in a Continuous Unrealized Loss Position, Total Estimated Fair Value	203,801	69,286
Securities in a Continuous Unrealized Loss Position, Total Unrealized Losses	(4,754)	(330)
Agency mortgage-backed pass-through securities
Debt Securities, Available-for-sale [Line Items]
Securities in a Continuous Unrealized Loss Position, Less than 12 months, Estimated Fair Value	92,920	28,659
Securities in a Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(1,565)	(146)
Securities in a Continuous Unrealized Loss Position, Total Estimated Fair Value	92,920	28,659
Securities in a Continuous Unrealized Loss Position, Total Unrealized Losses	(1,565)	(146)
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Securities in a Continuous Unrealized Loss Position, Less than 12 months, Estimated Fair Value	88,124	8,844
Securities in a Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(2,881)	(60)
Securities in a Continuous Unrealized Loss Position, Total Estimated Fair Value	88,124	8,844
Securities in a Continuous Unrealized Loss Position, Total Unrealized Losses	(2,881)	(60)
Agency collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Securities in a Continuous Unrealized Loss Position, Less than 12 months, Estimated Fair Value	11,842	11,629
Securities in a Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(212)	(39)
Securities in a Continuous Unrealized Loss Position, More than 12 Months, Estimated Fair Value	4,074	4,203
Securities in a Continuous Unrealized Loss Position, More than 12 Months Unrealized Losses	(34)	(36)
Securities in a Continuous Unrealized Loss Position, Total Estimated Fair Value	15,916	15,832
Securities in a Continuous Unrealized Loss Position, Total Unrealized Losses	(246)	(75)
Corporate bonds and other
Debt Securities, Available-for-sale [Line Items]
Securities in a Continuous Unrealized Loss Position, Less than 12 months, Estimated Fair Value	6,841	15,951
Securities in a Continuous Unrealized Loss Position, Less than 12 Months, Unrealized Losses	(62)	(49)
Securities in a Continuous Unrealized Loss Position, Total Estimated Fair Value	6,841	15,951
Securities in a Continuous Unrealized Loss Position, Total Unrealized Losses	$ (62)	$ (49)

LOANS AND ALLOWANCE FOR CREDI_3

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loan Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 4,659,169	$ 4,491,764
Allowance for credit losses on loans	(52,758)	(53,173)	$ (37,511)	$ (34,663)	$ (29,438)
Loans, net	4,606,411	4,438,591
Commercial real estate construction and land development
Accounts Notes And Loans Receivable [Line Items]
Allowance for credit losses on loans				(6,051)
1-4 family residential (including home equity)
Accounts Notes And Loans Receivable [Line Items]
Allowance for credit losses on loans				(5,452)
Residential construction
Accounts Notes And Loans Receivable [Line Items]
Allowance for credit losses on loans				$ (1,056)
Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	664,792	667,079
Allowance for credit losses on loans	(18,697)	(17,738)	(10,164)		(8,818)
Paycheck Protection Program (PPP)
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	728,424	569,901
Real estate | Commercial real estate (including multi-family residential)
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	2,018,853	1,999,877
Real estate | Commercial real estate construction and land development
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	386,637	367,213
Real estate | 1-4 family residential (including home equity)
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	726,228	737,605
Real estate | Residential construction
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	119,528	127,522
Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	14,707	22,567
Allowance for credit losses on loans	$ (279)	$ (413)	$ (118)		$ (120)

LOANS AND ALLOWANCE FOR CREDI_4

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Narrative (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2021USD ($)contractLoan	Mar. 31, 2020USD ($)contract	Dec. 31, 2020USD ($)	Jan. 01, 2020USD ($)	Dec. 31, 2019USD ($)
Accounts Notes And Loans Receivable [Line Items]
Accrued interest receivable for loans outstanding	$ 33,500,000		$ 34,500,000
Allowance for credit losses on loans	52,758,000	$ 37,511,000	53,173,000	$ 34,663,000	$ 29,438,000
Recorded investment	25,200,000		25,800,000
Change in method of calculating impairment	2,900,000		3,300,000
Troubled debt restructuring, write-down	0	394,000
Troubled debt restructuring, addition	174,000	441,000,000
Modification of outstanding recorded investment	$ 545,000	$ 1,252,000
Number of defaults on loan that were modified as troubled debt restructuring during the preceding 12 months | contract	1	4
COVID-19
Accounts Notes And Loans Receivable [Line Items]
Number of loans deferral due to CARES Act | Loan	65
Outstanding loan balances deferrals due to CARES Act	$ 62,100,000
Troubled debt restructurings added in reporting period
Accounts Notes And Loans Receivable [Line Items]
Recorded investment	545,000	$ 1,200,000
Unfunded Loan Commitment
Accounts Notes And Loans Receivable [Line Items]
Allowance for credit losses on loans	5,406,000		4,697,000
Non accrual loans interest income	$ 0		$ 0

LOANS AND ALLOWANCE FOR CREDI_5

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Aging Analysis of the Recorded Investment in Past Due Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	$ 21,162	$ 11,525
Nonaccrual Loans	35,051	28,893
Current Loans	4,602,956	4,451,346
Total loans evaluated for impairment	4,659,169	4,491,764
Financing Receivables, 30 to 89 Days Past Due
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	21,162	11,525
Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	3,941	2,486
Nonaccrual Loans	14,059	10,747
Current Loans	646,792	653,846
Total loans evaluated for impairment	664,792	667,079
Commercial and industrial | Financing Receivables, 30 to 89 Days Past Due
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	3,941	2,486
Paycheck Protection Program (PPP)
Accounts Notes And Loans Receivable [Line Items]
Current Loans	728,424	569,901
Total loans evaluated for impairment	728,424	569,901
Real estate | Commercial real estate (including multi-family residential)
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	8,712	3,063
Nonaccrual Loans	13,455	10,081
Current Loans	1,996,686	1,986,733
Total loans evaluated for impairment	2,018,853	1,999,877
Real estate | Commercial real estate (including multi-family residential) | Financing Receivables, 30 to 89 Days Past Due
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	8,712	3,063
Real estate | Commercial real estate construction and land development
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	5,691	2,930
Nonaccrual Loans	1,000	3,011
Current Loans	379,946	361,272
Total loans evaluated for impairment	386,637	367,213
Real estate | Commercial real estate construction and land development | Financing Receivables, 30 to 89 Days Past Due
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	5,691	2,930
Real estate | 1-4 family residential (including home equity)
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	2,488	3,000
Nonaccrual Loans	5,736	4,525
Current Loans	718,004	730,080
Total loans evaluated for impairment	726,228	737,605
Real estate | 1-4 family residential (including home equity) | Financing Receivables, 30 to 89 Days Past Due
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	2,488	3,000
Real estate | Residential construction
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	324
Current Loans	119,204	127,522
Total loans evaluated for impairment	119,528	127,522
Real estate | Residential construction | Financing Receivables, 30 to 89 Days Past Due
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	324
Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	6	46
Nonaccrual Loans	801	529
Current Loans	13,900	21,992
Total loans evaluated for impairment	14,707	22,567
Consumer and other | Financing Receivables, 30 to 89 Days Past Due
Accounts Notes And Loans Receivable [Line Items]
Loans Past Due and Still Accruing	$ 6	$ 46

LOANS AND ALLOWANCE FOR CREDI_6

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Risk Ratings by Category of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	$ 657,638
Term Loans Amortized Cost Basis by Origination Year, 2020	1,710,665
Term Loans Amortized Cost Basis by Origination Year, 2019	651,803
Term Loans Amortized Cost Basis by Origination Year, 2018	437,892
Term Loans Amortized Cost Basis by Origination Year, 2017	361,494
Term Loans Amortized Cost Basis by Origination Year, Prior	411,238
Revolving Loans	428,439
Total	4,659,169	$ 4,491,764
Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	52,615
Term Loans Amortized Cost Basis by Origination Year, 2020	152,288
Term Loans Amortized Cost Basis by Origination Year, 2019	85,036
Term Loans Amortized Cost Basis by Origination Year, 2018	54,469
Term Loans Amortized Cost Basis by Origination Year, 2017	24,705
Term Loans Amortized Cost Basis by Origination Year, Prior	30,737
Revolving Loans	264,942
Total	664,792	667,079
Paycheck Protection Program (PPP)
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	331,736
Term Loans Amortized Cost Basis by Origination Year, 2020	396,538
Term Loans Amortized Cost Basis by Origination Year, Prior	150
Total	728,424	569,901
Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	(11,511)
Term Loans Amortized Cost Basis by Origination Year, 2020	17,072
Term Loans Amortized Cost Basis by Origination Year, 2019	2,930
Term Loans Amortized Cost Basis by Origination Year, 2018	1,435
Term Loans Amortized Cost Basis by Origination Year, 2017	558
Term Loans Amortized Cost Basis by Origination Year, Prior	130
Revolving Loans	4,093
Total	14,707	22,567
Pass
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	626,808
Term Loans Amortized Cost Basis by Origination Year, 2020	1,586,882
Term Loans Amortized Cost Basis by Origination Year, 2019	553,068
Term Loans Amortized Cost Basis by Origination Year, 2018	371,140
Term Loans Amortized Cost Basis by Origination Year, 2017	282,514
Term Loans Amortized Cost Basis by Origination Year, Prior	308,095
Revolving Loans	385,714
Total	4,114,221	3,897,745
Pass | Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	42,316
Term Loans Amortized Cost Basis by Origination Year, 2020	130,986
Term Loans Amortized Cost Basis by Origination Year, 2019	74,052
Term Loans Amortized Cost Basis by Origination Year, 2018	45,122
Term Loans Amortized Cost Basis by Origination Year, 2017	17,573
Term Loans Amortized Cost Basis by Origination Year, Prior	25,166
Revolving Loans	235,233
Total	570,448	562,518
Pass | Paycheck Protection Program (PPP)
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	331,736
Term Loans Amortized Cost Basis by Origination Year, 2020	396,538
Term Loans Amortized Cost Basis by Origination Year, Prior	150
Total	728,424	569,901
Pass | Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	(11,511)
Term Loans Amortized Cost Basis by Origination Year, 2020	16,325
Term Loans Amortized Cost Basis by Origination Year, 2019	2,469
Term Loans Amortized Cost Basis by Origination Year, 2018	1,360
Term Loans Amortized Cost Basis by Origination Year, 2017	485
Term Loans Amortized Cost Basis by Origination Year, Prior	130
Revolving Loans	4,027
Total	13,285	21,359
Watch
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	15,870
Term Loans Amortized Cost Basis by Origination Year, 2020	65,011
Term Loans Amortized Cost Basis by Origination Year, 2019	52,115
Term Loans Amortized Cost Basis by Origination Year, 2018	29,494
Term Loans Amortized Cost Basis by Origination Year, 2017	36,229
Term Loans Amortized Cost Basis by Origination Year, Prior	45,618
Revolving Loans	22,103
Total	266,440	298,539
Watch | Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	4,886
Term Loans Amortized Cost Basis by Origination Year, 2020	8,079
Term Loans Amortized Cost Basis by Origination Year, 2019	5,314
Term Loans Amortized Cost Basis by Origination Year, 2018	4,381
Term Loans Amortized Cost Basis by Origination Year, 2017	1,198
Term Loans Amortized Cost Basis by Origination Year, Prior	1,839
Revolving Loans	15,629
Total	41,326	41,026
Watch | Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	53
Term Loans Amortized Cost Basis by Origination Year, 2019	161
Term Loans Amortized Cost Basis by Origination Year, 2018	3
Revolving Loans	63
Total	280	389
Special Mention
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	7,422
Term Loans Amortized Cost Basis by Origination Year, 2020	17,560
Term Loans Amortized Cost Basis by Origination Year, 2019	15,109
Term Loans Amortized Cost Basis by Origination Year, 2018	12,492
Term Loans Amortized Cost Basis by Origination Year, 2017	12,734
Term Loans Amortized Cost Basis by Origination Year, Prior	21,967
Revolving Loans	9,364
Total	96,648	115,226
Special Mention | Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	784
Term Loans Amortized Cost Basis by Origination Year, 2020	1,151
Term Loans Amortized Cost Basis by Origination Year, 2019	2,663
Term Loans Amortized Cost Basis by Origination Year, 2018	1,798
Term Loans Amortized Cost Basis by Origination Year, 2017	1,105
Term Loans Amortized Cost Basis by Origination Year, Prior	2,487
Revolving Loans	6,148
Total	16,136	25,010
Special Mention | Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	224
Term Loans Amortized Cost Basis by Origination Year, 2018	33
Revolving Loans	3
Total	260	270
Substandard
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	7,538
Term Loans Amortized Cost Basis by Origination Year, 2020	40,999
Term Loans Amortized Cost Basis by Origination Year, 2019	31,511
Term Loans Amortized Cost Basis by Origination Year, 2018	24,755
Term Loans Amortized Cost Basis by Origination Year, 2017	30,017
Term Loans Amortized Cost Basis by Origination Year, Prior	35,558
Revolving Loans	11,258
Total	181,636	180,114
Substandard | Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	4,629
Term Loans Amortized Cost Basis by Origination Year, 2020	11,859
Term Loans Amortized Cost Basis by Origination Year, 2019	3,007
Term Loans Amortized Cost Basis by Origination Year, 2018	3,157
Term Loans Amortized Cost Basis by Origination Year, 2017	4,829
Term Loans Amortized Cost Basis by Origination Year, Prior	1,245
Revolving Loans	7,932
Total	36,658	38,385
Substandard | Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	470
Term Loans Amortized Cost Basis by Origination Year, 2019	300
Term Loans Amortized Cost Basis by Origination Year, 2018	39
Term Loans Amortized Cost Basis by Origination Year, 2017	73
Total	882	549
Doubtful
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	213
Term Loans Amortized Cost Basis by Origination Year, 2018	11
Total	224	140
Doubtful | Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	213
Term Loans Amortized Cost Basis by Origination Year, 2018	11
Total	224	140
Commercial real estate (including multi-family residential)
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	169,313
Term Loans Amortized Cost Basis by Origination Year, 2020	644,110
Term Loans Amortized Cost Basis by Origination Year, 2019	368,363
Term Loans Amortized Cost Basis by Origination Year, 2018	242,269
Term Loans Amortized Cost Basis by Origination Year, 2017	247,063
Term Loans Amortized Cost Basis by Origination Year, Prior	295,386
Revolving Loans	52,349
Total	2,018,853	1,999,877
Commercial real estate (including multi-family residential) | Pass
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	153,677
Term Loans Amortized Cost Basis by Origination Year, 2020	586,634
Term Loans Amortized Cost Basis by Origination Year, 2019	296,323
Term Loans Amortized Cost Basis by Origination Year, 2018	200,738
Term Loans Amortized Cost Basis by Origination Year, 2017	190,080
Term Loans Amortized Cost Basis by Origination Year, Prior	212,707
Revolving Loans	47,193
Total	1,687,352	1,629,023
Commercial real estate (including multi-family residential) | Watch
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	6,612
Term Loans Amortized Cost Basis by Origination Year, 2020	25,111
Term Loans Amortized Cost Basis by Origination Year, 2019	39,322
Term Loans Amortized Cost Basis by Origination Year, 2018	17,722
Term Loans Amortized Cost Basis by Origination Year, 2017	23,039
Term Loans Amortized Cost Basis by Origination Year, Prior	36,873
Revolving Loans	1,956
Total	150,635	177,651
Commercial real estate (including multi-family residential) | Special Mention
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	6,115
Term Loans Amortized Cost Basis by Origination Year, 2020	11,053
Term Loans Amortized Cost Basis by Origination Year, 2019	8,007
Term Loans Amortized Cost Basis by Origination Year, 2018	6,003
Term Loans Amortized Cost Basis by Origination Year, 2017	10,328
Term Loans Amortized Cost Basis by Origination Year, Prior	14,462
Revolving Loans	647
Total	56,615	68,276
Commercial real estate (including multi-family residential) | Substandard
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	2,909
Term Loans Amortized Cost Basis by Origination Year, 2020	21,312
Term Loans Amortized Cost Basis by Origination Year, 2019	24,711
Term Loans Amortized Cost Basis by Origination Year, 2018	17,806
Term Loans Amortized Cost Basis by Origination Year, 2017	23,616
Term Loans Amortized Cost Basis by Origination Year, Prior	31,344
Revolving Loans	2,553
Total	124,251	124,927
Commercial real estate construction and land development
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	40,784
Term Loans Amortized Cost Basis by Origination Year, 2020	196,743
Term Loans Amortized Cost Basis by Origination Year, 2019	69,347
Term Loans Amortized Cost Basis by Origination Year, 2018	33,545
Term Loans Amortized Cost Basis by Origination Year, 2017	20,307
Term Loans Amortized Cost Basis by Origination Year, Prior	10,868
Revolving Loans	15,043
Total	386,637	367,213
Commercial real estate construction and land development | Pass
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	39,047
Term Loans Amortized Cost Basis by Origination Year, 2020	171,318
Term Loans Amortized Cost Basis by Origination Year, 2019	61,948
Term Loans Amortized Cost Basis by Origination Year, 2018	29,238
Term Loans Amortized Cost Basis by Origination Year, 2017	13,064
Term Loans Amortized Cost Basis by Origination Year, Prior	8,001
Revolving Loans	14,375
Total	336,991	320,133
Commercial real estate construction and land development | Watch
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	1,214
Term Loans Amortized Cost Basis by Origination Year, 2020	17,351
Term Loans Amortized Cost Basis by Origination Year, 2019	3,466
Term Loans Amortized Cost Basis by Origination Year, 2018	3,253
Term Loans Amortized Cost Basis by Origination Year, 2017	6,332
Term Loans Amortized Cost Basis by Origination Year, Prior	2,606
Total	34,222	39,021
Commercial real estate construction and land development | Special Mention
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	523
Term Loans Amortized Cost Basis by Origination Year, 2020	2,091
Term Loans Amortized Cost Basis by Origination Year, 2019	2,967
Term Loans Amortized Cost Basis by Origination Year, 2018	374
Term Loans Amortized Cost Basis by Origination Year, 2017	911
Term Loans Amortized Cost Basis by Origination Year, Prior	261
Revolving Loans	113
Total	7,240	2,880
Commercial real estate construction and land development | Substandard
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	5,983
Term Loans Amortized Cost Basis by Origination Year, 2019	966
Term Loans Amortized Cost Basis by Origination Year, 2018	680
Revolving Loans	555
Total	8,184	5,179
1-4 family residential (including home equity)
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	58,447
Term Loans Amortized Cost Basis by Origination Year, 2020	215,079
Term Loans Amortized Cost Basis by Origination Year, 2019	118,414
Term Loans Amortized Cost Basis by Origination Year, 2018	100,908
Term Loans Amortized Cost Basis by Origination Year, 2017	68,131
Term Loans Amortized Cost Basis by Origination Year, Prior	73,237
Revolving Loans	92,012
Total	726,228	737,605
1-4 family residential (including home equity) | Pass
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	55,339
Term Loans Amortized Cost Basis by Origination Year, 2020	199,484
Term Loans Amortized Cost Basis by Origination Year, 2019	111,305
Term Loans Amortized Cost Basis by Origination Year, 2018	89,416
Term Loans Amortized Cost Basis by Origination Year, 2017	60,582
Term Loans Amortized Cost Basis by Origination Year, Prior	61,211
Revolving Loans	84,886
Total	662,223	670,074
1-4 family residential (including home equity) | Watch
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	3,108
Term Loans Amortized Cost Basis by Origination Year, 2020	11,833
Term Loans Amortized Cost Basis by Origination Year, 2019	3,110
Term Loans Amortized Cost Basis by Origination Year, 2018	4,135
Term Loans Amortized Cost Basis by Origination Year, 2017	5,660
Term Loans Amortized Cost Basis by Origination Year, Prior	4,300
Revolving Loans	4,455
Total	36,601	37,667
1-4 family residential (including home equity) | Special Mention
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	2,387
Term Loans Amortized Cost Basis by Origination Year, 2019	1,472
Term Loans Amortized Cost Basis by Origination Year, 2018	4,284
Term Loans Amortized Cost Basis by Origination Year, 2017	390
Term Loans Amortized Cost Basis by Origination Year, Prior	4,757
Revolving Loans	2,453
Total	15,743	18,790
1-4 family residential (including home equity) | Substandard
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	1,375
Term Loans Amortized Cost Basis by Origination Year, 2019	2,527
Term Loans Amortized Cost Basis by Origination Year, 2018	3,073
Term Loans Amortized Cost Basis by Origination Year, 2017	1,499
Term Loans Amortized Cost Basis by Origination Year, Prior	2,969
Revolving Loans	218
Total	11,661	11,074
Residential construction
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	16,254
Term Loans Amortized Cost Basis by Origination Year, 2020	88,835
Term Loans Amortized Cost Basis by Origination Year, 2019	7,713
Term Loans Amortized Cost Basis by Origination Year, 2018	5,266
Term Loans Amortized Cost Basis by Origination Year, 2017	730
Term Loans Amortized Cost Basis by Origination Year, Prior	730
Total	119,528	127,522
Residential construction | Pass
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	16,204
Term Loans Amortized Cost Basis by Origination Year, 2020	85,597
Term Loans Amortized Cost Basis by Origination Year, 2019	6,971
Term Loans Amortized Cost Basis by Origination Year, 2018	5,266
Term Loans Amortized Cost Basis by Origination Year, 2017	730
Term Loans Amortized Cost Basis by Origination Year, Prior	730
Total	115,498	124,737
Residential construction | Watch
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2021	50
Term Loans Amortized Cost Basis by Origination Year, 2020	2,584
Term Loans Amortized Cost Basis by Origination Year, 2019	742
Total	3,376	$ 2,785
Residential construction | Special Mention
Accounts Notes And Loans Receivable [Line Items]
Term Loans Amortized Cost Basis by Origination Year, 2020	654
Total	$ 654

LOANS AND ALLOWANCE FOR CREDI_7

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Risk Ratings by Category of Loans (Parenthetical) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Paycheck Protection Program (PPP)
Accounts Notes And Loans Receivable [Line Items]
Net deferred fees	$ 22	$ 13.9

LOANS AND ALLOWANCE FOR CREDI_8

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Allowance for credit losses on loans:
Balance, beginning of period	$ 53,173	$ 29,438
Provision for loan losses	(70)	10,990
Charge-offs	(404)	(3,132)
Recoveries	59	215
Net charge-offs	(345)	(2,917)
Balance, end of period	52,758	37,511
Commercial and industrial
Allowance for credit losses on loans:
Balance, beginning of period	17,738	8,818
Provision for loan losses	1,304	1,865
Charge-offs	(404)	(734)
Recoveries	59	215
Net charge-offs	(345)	(519)
Balance, end of period	18,697	10,164
Commercial Real Estate Portfolio Segment | Commercial real estate (including multi-family residential)
Allowance for credit losses on loans:
Balance, beginning of period	23,934	11,170
Provision for loan losses	(155)	5,725
Charge-offs		(144)
Net charge-offs		(144)
Balance, end of period	23,779	16,751
Commercial Real Estate Portfolio Segment | Commercial real estate construction and land development
Allowance for credit losses on loans:
Balance, beginning of period	6,939	4,421
Provision for loan losses	683	732
Charge-offs		(2,164)
Net charge-offs		(2,164)
Balance, end of period	7,622	2,989
Commercial Real Estate Portfolio Segment | 1-4 family residential (including home equity)
Allowance for credit losses on loans:
Balance, beginning of period	3,279	3,852
Provision for loan losses	(1,723)	2,296
Charge-offs		(90)
Net charge-offs		(90)
Balance, end of period	1,556	6,058
Commercial Real Estate Portfolio Segment | Residential construction
Allowance for credit losses on loans:
Balance, beginning of period	870	1,057
Provision for loan losses	(45)	374
Balance, end of period	825	1,431
Consumer and other
Allowance for credit losses on loans:
Balance, beginning of period	413	120
Provision for loan losses	(134)	(2)
Balance, end of period	$ 279	$ 118

LOANS AND ALLOWANCE FOR CREDI_9

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Activity in Allowance for Credit Losses on Unfunded Commitments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Allowance For Loan Commitments [Line Items]
Balance, beginning of period	$ 53,173
Balance, end of period	52,758
Unfunded Loan Commitment
Allowance For Loan Commitments [Line Items]
Balance, beginning of period	4,697
Provision for credit losses on unfunded commitments	709
Balance, end of period	$ 5,406

LOANS AND ALLOWANCE FOR CRED_10

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Amortized Cost Basis of Collateral Dependent Loans Individually Evaluated to Determine Expected Credit Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	$ 16,178	$ 8,683
Real Estate
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	7,279	3,526
Business Assets
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	8,619	5,157
Other
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	280
Commercial and industrial
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	8,619	5,157
Commercial and industrial | Business Assets
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	8,619	5,157
Real estate | Commercial real estate (including multi-family residential)
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	707	425
Real estate | Commercial real estate construction and land development
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	1,000
Real estate | 1-4 family residential (including home equity)
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	5,572	3,101
Real estate | Real Estate | Commercial real estate (including multi-family residential)
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	707	425
Real estate | Real Estate | Commercial real estate construction and land development
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	1,000
Real estate | Real Estate | 1-4 family residential (including home equity)
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	5,572	$ 3,101
Consumer and other
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	280
Consumer and other | Other
Financing Receivable Allowance For Credit Losses [Line Items]
Finance receivables allowance of credit losses	$ 280

LOANS AND ALLOWANCE FOR CRED_11

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Nonaccrual Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Financing Receivable Nonaccrual Status [Line Items]
Nonaccrual Loans with No Related Allowance	$ 13,882	$ 15,194
Nonaccrual Loans with Related Allowance	21,169	13,699
Total Nonaccrual Loans	35,051	28,893
Commercial and industrial
Financing Receivable Nonaccrual Status [Line Items]
Nonaccrual Loans with No Related Allowance	2,906	2,097
Nonaccrual Loans with Related Allowance	11,153	8,650
Total Nonaccrual Loans	14,059	10,747
Real estate | Commercial real estate (including multi-family residential)
Financing Receivable Nonaccrual Status [Line Items]
Nonaccrual Loans with No Related Allowance	4,191	7,487
Nonaccrual Loans with Related Allowance	9,264	2,594
Total Nonaccrual Loans	13,455	10,081
Real estate | Commercial real estate construction and land development
Financing Receivable Nonaccrual Status [Line Items]
Nonaccrual Loans with No Related Allowance	1,000	2,958
Nonaccrual Loans with Related Allowance		53
Total Nonaccrual Loans	1,000	3,011
Real estate | 1-4 family residential (including home equity)
Financing Receivable Nonaccrual Status [Line Items]
Nonaccrual Loans with No Related Allowance	5,160	2,652
Nonaccrual Loans with Related Allowance	576	1,873
Total Nonaccrual Loans	5,736	4,525
Consumer and other
Financing Receivable Nonaccrual Status [Line Items]
Nonaccrual Loans with No Related Allowance	625
Nonaccrual Loans with Related Allowance	176	529
Total Nonaccrual Loans	$ 801	$ 529

LOANS AND ALLOWANCE FOR CRED_12

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)contract	Mar. 31, 2020USD ($)contract
Accounts Notes And Loans Receivable [Line Items]
Number of Contracts | contract	1	7
Pre-Modification of Outstanding Recorded Investment	$ 545	$ 1,252
Post Modification of Outstanding Recorded Investment	$ 545	$ 1,252
Paycheck Protection Program (PPP)
Accounts Notes And Loans Receivable [Line Items]
Number of Contracts | contract	0	0
Pre-Modification of Outstanding Recorded Investment	$ 0	$ 0
Post Modification of Outstanding Recorded Investment	$ 0	$ 0
Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Number of Contracts | contract	0	5
Pre-Modification of Outstanding Recorded Investment	$ 0	$ 1,104
Post Modification of Outstanding Recorded Investment	$ 0	$ 1,104
Real estate | Commercial real estate (including multi-family residential)
Accounts Notes And Loans Receivable [Line Items]
Number of Contracts | contract	1	0
Pre-Modification of Outstanding Recorded Investment	$ 545	$ 0
Post Modification of Outstanding Recorded Investment	$ 545	$ 0
Real estate | Commercial real estate construction and land development
Accounts Notes And Loans Receivable [Line Items]
Number of Contracts | contract	0	0
Pre-Modification of Outstanding Recorded Investment	$ 0	$ 0
Post Modification of Outstanding Recorded Investment	$ 0	$ 0
Real estate | 1-4 family residential (including home equity)
Accounts Notes And Loans Receivable [Line Items]
Number of Contracts | contract	0	1
Pre-Modification of Outstanding Recorded Investment	$ 0	$ 118
Post Modification of Outstanding Recorded Investment	$ 0	$ 118
Real estate | Residential construction
Accounts Notes And Loans Receivable [Line Items]
Number of Contracts | contract	0	0
Pre-Modification of Outstanding Recorded Investment	$ 0	$ 0
Post Modification of Outstanding Recorded Investment	$ 0	$ 0
Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Number of Contracts | contract	0	1
Pre-Modification of Outstanding Recorded Investment	$ 0	$ 30
Post Modification of Outstanding Recorded Investment	$ 0	$ 30

LOANS AND ALLOWANCE FOR CRED_13

LOANS AND ALLOWANCE FOR CREDIT LOSSES - Schedule of Principal and Interest Deferrals Associated with Loan Modifications Related to COVID 19 (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 4,659,169	$ 4,491,764
Initial Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 1,063,973
Percentage of Total Deferrals	100.00%
Additional Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 237,805
Percentage of Total Deferrals	100.00%
Remaining Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 62,120
Percentage of Total Deferrals	100.00%
Commercial and industrial
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 664,792	667,079
Commercial and industrial | Initial Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 109,866
Percentage of Total Deferrals	10.30%
Commercial and industrial | Additional Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 22,134
Percentage of Total Deferrals	9.30%
Commercial and industrial | Remaining Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 6,398
Percentage of Total Deferrals	10.30%
Paycheck Protection Program (PPP)
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 728,424	569,901
Paycheck Protection Program (PPP) | Initial Deferrals
Accounts Notes And Loans Receivable [Line Items]
Percentage of Total Deferrals	0.00%
Paycheck Protection Program (PPP) | Additional Deferrals
Accounts Notes And Loans Receivable [Line Items]
Percentage of Total Deferrals	0.00%
Paycheck Protection Program (PPP) | Remaining Deferrals
Accounts Notes And Loans Receivable [Line Items]
Percentage of Total Deferrals	0.00%
Consumer and other
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 14,707	22,567
Consumer and other | Initial Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 805
Percentage of Total Deferrals	0.10%
Consumer and other | Additional Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 157
Percentage of Total Deferrals	0.10%
Consumer and other | Remaining Deferrals
Accounts Notes And Loans Receivable [Line Items]
Percentage of Total Deferrals	0.00%
Commercial real estate (including multi-family residential) | Real estate
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 2,018,853	1,999,877
Commercial real estate (including multi-family residential) | Real estate | Initial Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 761,179
Percentage of Total Deferrals	71.50%
Commercial real estate (including multi-family residential) | Real estate | Additional Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 182,662
Percentage of Total Deferrals	76.80%
Commercial real estate (including multi-family residential) | Real estate | Remaining Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 48,646
Percentage of Total Deferrals	78.30%
Commercial real estate construction and land development | Real estate
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 386,637	367,213
Commercial real estate construction and land development | Real estate | Initial Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 81,566
Percentage of Total Deferrals	7.70%
Commercial real estate construction and land development | Real estate | Additional Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 19,991
Percentage of Total Deferrals	8.40%
Commercial real estate construction and land development | Real estate | Remaining Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 2,613
Percentage of Total Deferrals	4.20%
1-4 family residential (including home equity) | Real estate
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 726,228	737,605
1-4 family residential (including home equity) | Real estate | Initial Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 108,870
Percentage of Total Deferrals	10.20%
1-4 family residential (including home equity) | Real estate | Additional Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 12,700
Percentage of Total Deferrals	5.30%
1-4 family residential (including home equity) | Real estate | Remaining Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 4,463
Percentage of Total Deferrals	7.20%
Residential construction | Real estate
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 119,528	$ 127,522
Residential construction | Real estate | Initial Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 1,687
Percentage of Total Deferrals	0.20%
Residential construction | Real estate | Additional Deferrals
Accounts Notes And Loans Receivable [Line Items]
Deferred Loan Balance	$ 161
Percentage of Total Deferrals	0.10%
Residential construction | Real estate | Remaining Deferrals
Accounts Notes And Loans Receivable [Line Items]
Percentage of Total Deferrals	0.00%

LEASES - Narrative (Details)

LEASES - Narrative (Details)	3 Months Ended
	Mar. 31, 2021BranchLocationandOfficeSpace
Lessee Lease Description [Line Items]
Number of leased branch locations and office space	15
Operating lease, existence of option to extend	true
Maximum
Lessee Lease Description [Line Items]
Lessee, operating Lease, term of contract	12 months
Operating lease renewal term	5 years
Minimum
Lessee Lease Description [Line Items]
Operating lease renewal term	1 year

LEASES - Supplemental Lease Inf

LEASES - Supplemental Lease Information (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheet:
Operating lease right of use asset classified as premises and equipment	$ 11,399	$ 11,610
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Premises and equipment, net	Premises and equipment, net
Operating lease liability classified as other liabilities	$ 11,625	$ 11,850
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Other liabilities	Other liabilities
Weighted average lease term, in years	5 years 4 months 24 days	5 years 6 months 21 days
Weighted average discount rate	2.77%	2.86%

LEASES - Summary of Lease Costs

LEASES - Summary of Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement:
Operating lease cost	$ 873	$ 799
Short-term lease cost	15	36
Sublease income	(18)	(18)
Total operating lease costs	$ 870	$ 817

LEASES - Maturity Analysis of L

LEASES - Maturity Analysis of Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Lease payments due:
Within one year	$ 3,132	$ 3,068
After one but within two years	2,539	2,664
After two but within three years	2,120	2,056
After three but within four years	1,490	1,591
After four but within five years	1,069	1,057
After five years	2,144	2,355
Total lease payments	12,494	12,791
Discount on cash flows	869	941
Total lease liability	$ 11,625	$ 11,850

FAIR VALUE - Carrying Amounts a

FAIR VALUE - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 624,330	$ 422,766
Available for sale securities	787,516	772,890
Loans held for investment, net of allowance	4,606,411	4,438,591
Interest rate swap	572	1,252
Accrued interest receivable	38,632	40,053
Deposits	5,374,189	4,988,482
Accrued interest payable	3,862	2,701
Borrowed funds	147,517	155,515
Subordinated debt	108,453	108,322
Estimated Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	624,330	422,766
Available for sale securities	787,516	772,890
Loans held for investment, net of allowance	4,605,252	4,431,816
Interest rate swap	572	1,252
Accrued interest receivable	38,632	40,053
Deposits	5,383,876	5,003,594
Accrued interest payable	3,862	2,701
Borrowed funds	132,123	144,629
Subordinated debt	109,935	109,832
Estimated Fair Value | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	624,330	422,766
Available for sale securities	0	0
Loans held for investment, net of allowance	0	0
Interest rate swap	0	0
Accrued interest receivable	3	2
Deposits	0	0
Accrued interest payable	0	0
Borrowed funds	0	0
Subordinated debt	0	0
Estimated Fair Value | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Available for sale securities	787,516	772,890
Loans held for investment, net of allowance	0	0
Interest rate swap	572	1,252
Accrued interest receivable	5,133	5,531
Deposits	5,383,876	5,003,594
Accrued interest payable	3,862	2,701
Borrowed funds	132,123	144,629
Subordinated debt	109,935	109,832
Estimated Fair Value | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Available for sale securities	0	0
Loans held for investment, net of allowance	4,605,252	4,431,816
Interest rate swap	0	0
Accrued interest receivable	33,496	34,520
Deposits	0	0
Accrued interest payable	0	0
Borrowed funds	0	0
Subordinated debt	$ 0	$ 0

FAIR VALUE - Narrative (Details

FAIR VALUE - Narrative (Details)	3 Months Ended
	Mar. 31, 2021USD ($)Property	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)Property
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate acquired through foreclosure	$ 576,000		$ 9,196,000
Foreclosed Residential Rental Property
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of properties | Property	1		1
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real estate acquired through foreclosure	$ 576,000		$ 9,200,000
Collateral Dependent Loans Specific Allocation of Allowance for Credit Losses on Loans | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of estimated selling and closing costs of collateral	5.00%
Collateral Dependent Loans Specific Allocation of Allowance for Credit Losses on Loans | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of estimated selling and closing costs of collateral	10.00%
Other Real Estate Owned | Minimum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of estimated selling and closing costs of collateral	5.00%
Other Real Estate Owned | Maximum
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Percentage of estimated selling and closing costs of collateral	10.00%
Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	$ 0
Transfers of assets between Level 1 and Level 2	0	$ 0
Transfers of assets between Level 2 and Level 1	0	0
Transfers of assets into Level 3	0	0
Transfers of assets out of Level 3	0	0
Transfers of liabilities between Level 1 and Level 2	0	0
Transfers of liabilities between Level 2 and Level 3	0	0
Transfers of liabilities into Level 3	0	0
Transfers of liabilities out of Level 3	0	$ 0
Nonrecurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial liabilities	$ 0		$ 0

FAIR VALUE - Fair Values for As

FAIR VALUE - Fair Values for Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	$ 787,516	$ 772,890
U.S. government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	24,992	26,199
Municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	446,001	427,605
Agency mortgage-backed pass-through securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	173,673	171,289
Agency collateralized mortgage obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	82,037	84,370
Corporate bonds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	60,813	63,427
Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	787,516	772,890
Recurring Basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	787,516	772,890
Recurring Basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | U.S. government and agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	24,992	26,199
Recurring Basis | U.S. government and agency securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | U.S. government and agency securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	24,992	26,199
Recurring Basis | U.S. government and agency securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Municipal securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	446,001	427,605
Recurring Basis | Municipal securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Municipal securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	446,001	427,605
Recurring Basis | Municipal securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Agency mortgage-backed pass-through securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	173,673	171,289
Recurring Basis | Agency mortgage-backed pass-through securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Agency mortgage-backed pass-through securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	173,673	171,289
Recurring Basis | Agency mortgage-backed pass-through securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Agency collateralized mortgage obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	82,037	84,370
Recurring Basis | Agency collateralized mortgage obligations | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Agency collateralized mortgage obligations | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	82,037	84,370
Recurring Basis | Agency collateralized mortgage obligations | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Corporate bonds and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	60,813	63,427
Recurring Basis | Corporate bonds and other | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Corporate bonds and other | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	60,813	63,427
Recurring Basis | Corporate bonds and other | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available for sale securities	0	0
Recurring Basis | Interest rate swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap	572	1,252
Recurring Basis | Interest rate swap | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap	0	0
Recurring Basis | Interest rate swap | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap	572	1,252
Recurring Basis | Interest rate swap | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap	$ 0	$ 0

FAIR VALUE - Assets Measured at

FAIR VALUE - Assets Measured at Fair Value on a Nonrecurring Basis (Details) - Nonrecurring Basis - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned	$ 0	$ 0
Assets and liabilities are measured at fair value, nonrecurring basis	0	0
Level 1 | Commercial and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 1 | Commercial real estate (including multi-family residential)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 1 | Consumer and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 1 | Commercial real estate construction and land development
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 1 | 1-4 family residential (including home equity)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 1 | Residential construction
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned	0	0
Assets and liabilities are measured at fair value, nonrecurring basis	0	0
Level 2 | Commercial and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 2 | Commercial real estate (including multi-family residential)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 2 | Consumer and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 2 | Commercial real estate construction and land development
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 2 | 1-4 family residential (including home equity)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 2 | Residential construction
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other real estate owned	576	9,196
Assets and liabilities are measured at fair value, nonrecurring basis	21,745	22,895
Level 3 | Commercial and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	11,153	8,650
Level 3 | Commercial real estate (including multi-family residential)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	9,264	2,594
Level 3 | Consumer and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	176	529
Level 3 | Commercial real estate construction and land development
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	0	53
Level 3 | 1-4 family residential (including home equity)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	576	1,873
Level 3 | Residential construction
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral Dependent Loans:	$ 0	$ 0

DEPOSITS - Narrative (Details)

DEPOSITS - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Deposit Liabilities [Abstract]
Time deposits, at or above FDIC insurance limit	$ 250	$ 250
Time deposits 250,000 or more	782,100	726,800
Brokered deposits	$ 433,200	$ 453,800

DEPOSITS - Time Deposits by Mat

DEPOSITS - Time Deposits by Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Deposit Liabilities [Abstract]
Within one year	$ 868,760
After one but within two years	367,037
After two but within three years	68,547
After three but within four years	28,664
After four but within five years	28,527
Total	$ 1,361,535	$ 1,346,649

DERIVATIVE INSTRUMENTS - Summar

DERIVATIVE INSTRUMENTS - Summary of Cash Flow Hedge Relationships (Detail) - Interest rate swaps - Other Assets - Cash Flow Hedging - Designated as Hedging Instrument	3 Months Ended
	Mar. 31, 2021USD ($)
Derivatives Fair Value [Line Items]
Weighted Average Maturity (In Years)	4 years 7 days
Weighted Average Pay Rate	0.64%
Receive Rate	3 month LIBOR
Notional Amount	$ 100,000,000
Estimated Fair Value	$ 572,000

DERIVATIVE INSTRUMENTS - Effect

DERIVATIVE INSTRUMENTS - Effect of Cash Flow Hedge Relationship on Statement of Comprehensive Income (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Cash Flow Hedging | Designated as Hedging Instrument | Interest rate swap
Derivative Instruments Gain Loss [Line Items]
Amount of Loss Recognized in Other Comprehensive Income	$ 1,824

DERIVATIVE INSTRUMENTS - Narrat

DERIVATIVE INSTRUMENTS - Narrative (Details) - Cash Flow Hedging - Designated as Hedging Instrument $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Derivative Instruments Gain Loss [Line Items]
Unrealized loss reclassified as interest expense during the next twelve months	$ (91)
Losses, net of tax reclassified from accumulated other comprehensive income into net income	$ 72

BORROWINGS AND BORROWING CAPA_2

BORROWINGS AND BORROWING CAPACITY - Narrative (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 28, 2018
Revolving Credit Agreement
Debt Instrument [Line Items]
Outstanding amount	$ 7,600,000
Amended Revolving Credit Agreement
Debt Instrument [Line Items]
Debt instrument maturity, month and year	2025-12
Percentage of debt secured by capital stock	100.00%
Borrowing Agreement | Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.25%
Interest rate, effective percentage	3.00%
Credit Facility With Another Financial Institution | Amended Revolving Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 45,000,000
Annual reduction in borrowing capacity		$ 7,500,000
Federal Home Loan Bank of Dallas
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 2,000,000,000
Remaining borrowing capacity	1,330,000,000
Outstanding amount	672,100,000
Letters of credit, outstanding amount	532,100,000
Federal Home Loan Bank of Dallas | Expire in Remaining Month of 2021
Debt Instrument [Line Items]
Letters of credit, outstanding amount	218,500,000
Federal Home Loan Bank of Dallas | Expire in 2022
Debt Instrument [Line Items]
Letters of credit, outstanding amount	258,000,000
Federal Home Loan Bank of Dallas | Expire in 2023
Debt Instrument [Line Items]
Letters of credit, outstanding amount	19,400,000
Federal Home Loan Bank of Dallas | Expire in 2024
Debt Instrument [Line Items]
Letters of credit, outstanding amount	36,200,000
Federal Home Loan Bank of Dallas | Short-term Debt
Debt Instrument [Line Items]
Federal Home Loan Bank, advances	$ 140,000,000
Federal Home Loan Bank of Dallas | Short-term Debt | Weighted Average
Debt Instrument [Line Items]
Federal Home Loan Bank, advances, interest rate	1.19%

SUBORDINATED DEBT - Narrative (

SUBORDINATED DEBT - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended
	Sep. 30, 2019	Dec. 31, 2017	Mar. 31, 2021	Jan. 01, 2015
Subordinated Borrowing [Line Items]
Junior subordinated debt owed to trusts			$ 11,341
Subordinated Notes | Fixed-to-Floating Rate Subordinated Notes
Subordinated Borrowing [Line Items]
Debt instrument, face amount	$ 60,000	$ 40,000
Issuance price, percentage	100.00%	100.00%
Proceeds from issuance of debt	$ 58,600	$ 39,400
Stated percentage	4.70%	5.25%
Redemption price, percentage	100.00%	100.00%
Subordinated Notes | Fixed-to-Floating Rate Subordinated Notes | 3 month LIBOR
Subordinated Borrowing [Line Items]
Basis spread on variable rate	3.13%	3.03%
F&M Bancshares. Inc. | Junior Subordinated Debt
Subordinated Borrowing [Line Items]
Debentures, period over which company may defer interest payments			5 years
Debt instrument, face amount			$ 11,300
Debt instrument, carrying value			$ 9,700
Debt instrument, unamortized discount				$ 2,500

SUBORDINATED DEBT - Summary of

SUBORDINATED DEBT - Summary of Pertinent Information Related to Junior Subordinated Debentures (Details)	3 Months Ended
	Mar. 31, 2021USD ($)
Subordinated Borrowing [Line Items]
Junior Subordinated Debt Owed to Trusts	$ 11,341,000
Junior Subordinated Debt | 3 month LIBOR
Subordinated Borrowing [Line Items]
Interest rate, period end	0.18962%
Junior Subordinated Debt | Farmers & Merchants Capital Trust II
Subordinated Borrowing [Line Items]
Issuance Date	Nov. 13, 2003
Trust Preferred Securities Outstanding	$ 7,500,000
Junior Subordinated Debt Owed to Trusts	$ 7,732,000
Maturity Date	Nov. 8, 2033	[1]
Junior Subordinated Debt | Farmers & Merchants Capital Trust II | 3 month LIBOR
Subordinated Borrowing [Line Items]
Basis spread on variable rate	3.00%	[2]
Junior Subordinated Debt | Farmers & Merchants Capital Trust III
Subordinated Borrowing [Line Items]
Issuance Date	Jun. 30, 2005
Trust Preferred Securities Outstanding	$ 3,500,000
Junior Subordinated Debt Owed to Trusts	$ 3,609,000
Maturity Date	Jul. 7, 2035	[1]
Junior Subordinated Debt | Farmers & Merchants Capital Trust III | 3 month LIBOR
Subordinated Borrowing [Line Items]
Basis spread on variable rate	1.80%	[2]
[1]	All debentures are currently callable.
[2]	The 3-month LIBOR in effect as of March 31, 2021 was 0.18962%.

INCOME TAXES (Details)

INCOME TAXES (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income tax expense	$ 3,866,000	$ 843,000
Effective income tax rate reconciliation, percent	17.70%	19.30%
Unrecognized tax benefits, income tax penalties and interest expense	$ 0

STOCK BASED COMPENSATION - Narr

STOCK BASED COMPENSATION - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	3,200,000
Share-based compensation expense	$ 820	$ 804
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	1,800,000
Option, cumulative options granted since inception (in shares)	1,309,231
Expiration period	10 years
Award vesting period	4 years
Unrecognized compensation cost	$ 67
Weighted average period over which unrecognized compensation	5 months 12 days
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Unrecognized compensation cost	$ 6,400
Weighted average period over which unrecognized compensation	2 years 9 months 14 days
Equity instruments other than options, grants in period (in shares)	67,341
Share awards granted (in shares)	67,000
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
Weighted average period over which unrecognized compensation	2 years 6 months
Service period	1 year
Share awards granted (in shares)	56,255	34,628
Unrecognized compensation expense	$ 3,200

STOCK BASED COMPENSATION - Stoc

STOCK BASED COMPENSATION - Stock Option Plans Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Number of Options
Options outstanding, beginning balance (in shares)	469
Options exercised (in shares)	(71)
Options outstanding, ending balance (in shares)	398	469
Number of options vested and exercisable (in shares)	389
Weighted Average Exercise Price
Options outstanding, beginning balance (in dollars per share)	$ 21.08
Options exercised (in dollars per share)	18.77
Options outstanding, ending balance (in dollars per share)	21.45	$ 21.08
Weighted Average Exercise Price, Options vested and exercisable (in dollars per share)	$ 21.01
Weighted Average Remaining Contractual Term, Options outstanding	3 years 3 months 29 days	3 years 5 months 4 days
Weighted Average Remaining Contractual Term, Options vested and exercisable	3 years 3 months 7 days
Aggregate Intrinsic Value, Options outstanding	$ 7,573	$ 6,118
Aggregate Intrinsic Value, Options vested and exercisable	$ 7,604

STOCK BASED COMPENSATION - Summ

STOCK BASED COMPENSATION - Summary of Restricted Stock Activity (Details) - Restricted Stock shares in Thousands	3 Months Ended
	Mar. 31, 2021$ / sharesshares
Number of Shares
Nonvested share awards outstanding, beginning balance (in shares) | shares	158
Share awards granted (in shares) | shares	67
Share awards vested (in shares) | shares	(3)
Unvested share awards forfeited or cancelled (in shares) | shares	(3)
Nonvested share awards outstanding, ending balance (in shares) | shares	219
Weighted Average Grant Date Fair Value
Nonvested share awards outstanding, beginning balance (in dollars per share) | $ / shares	$ 30.78
Share awards granted (in dollars per share) | $ / shares	38.47
Share awards vested (in dollars per share) | $ / shares	34.85
Unvested share awards forfeited or cancelled (in dollars per share) | $ / shares	37.18
Nonvested share awards outstanding, ending balance | $ / shares	$ 33.03

OFF-BALANCE SHEET ARRANGEMENT_3

OFF-BALANCE SHEET ARRANGEMENTS, COMMITMENTS AND CONTINGENCIES - Contractual Amounts of Financial Instruments With Off-balance Sheet Risk (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fixed Rate	$ 936,049	$ 771,190
Variable Rate	513,659	488,070
Commitments to extend credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fixed Rate	926,569	761,938
Variable Rate	506,396	480,067
Standby letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fixed Rate	9,480	9,252
Variable Rate	$ 7,263	$ 8,003

OFF-BALANCE SHEET ARRANGEMENT_4

OFF-BALANCE SHEET ARRANGEMENTS, COMMITMENTS AND CONTINGENCIES - Narrative (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments to make loans, period	120 days
Off-balance-sheet fixed rate loan commitments, weighted average maturity	3 years 6 months 10 days	3 years 6 months 10 days
Minimum
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance-sheet fixed rate loan commitments, interest rate	1.20%	1.20%
Maximum
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance-sheet fixed rate loan commitments, interest rate	13.49%	18.00%
Weighted Average
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance-sheet fixed rate loan commitments, interest rate	5.07%	5.13%

REGULATORY CAPITAL MATTERS - Na

REGULATORY CAPITAL MATTERS - Narrative (Details)	Mar. 31, 2021
Regulatory Capital Matters [Abstract]
Capital conservation buffer	2.50%

REGULATORY CAPITAL MATTERS - Ac

REGULATORY CAPITAL MATTERS - Actual and Required Capital (Details) $ in Thousands	Mar. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Total Capital
Capital	$ 656,264	$ 642,155
Capital to Risk Weighted Assets	0.1572	0.1571
Capital Required for Capital Adequacy	$ 333,986	$ 327,084
Capital Required for Capital Adequacy to Risk Weighted Assets	0.0800	0.0800
Plus Capital Conservation Buffer	$ 438,356	$ 429,298
Plus Capital Conservation Buffer to Risk Weighted Assets	0.1050	0.1050
Common Equity Tier 1 Capital
Common Equity Tier 1 Risk Based Capital	$ 495,552	$ 482,643
Common Equity Tier 1 Risk Based Capital to Risk Weighted Assets	0.1187	0.1180
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy	$ 187,867	$ 183,985
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	0.0450	0.0450
Plus Common Equity Tier 1 Risk Based Capital	$ 292,237	$ 286,199
Plus Common Equity Tier 1 Risk Based Capital to Risk Weighted Assets	0.0700	0.0700
Tier 1 Capital
Tier 1 Risk Based Capital	$ 505,218	$ 492,281
Tier 1 Risk Based Capital to Risk Weighted Assets	0.1210	0.1204
Tier 1 Risk Based Capital Required for Capital Adequacy	$ 250,489	$ 245,313
Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	0.0600	0.0600
Plus Tier 1 Risk Based Capital	$ 354,860	$ 347,527
Plus Tier 1 Risk Based Capital to Risk Weighted Assets	0.0850	0.0850
Tier 1 Capital
Tier 1 Leverage Capital	$ 505,218	$ 492,281
Tier 1 Leverage Capital to Average Assets	0.0857	0.0851
Tier 1 Leverage Capital Required for Capital Adequacy	$ 235,803	$ 231,518
Tier 1 Leverage Capital Required for Capital Adequacy to Average Assets	0.0400	0.0400
Plus Tier 1 Leverage Capital	$ 235,803	$ 231,518
Plus Tier 1 Leverage Capital to Average Assets	0.0400	0.0400
Allegiance Bank
Total Capital
Capital	$ 641,160	$ 635,223
Capital to Risk Weighted Assets	0.1537	0.1555
Capital Required for Capital Adequacy	$ 333,627	$ 326,804
Capital Required for Capital Adequacy to Risk Weighted Assets	0.0800	0.0800
Plus Capital Conservation Buffer	$ 437,886	$ 428,931
Plus Capital Conservation Buffer to Risk Weighted Assets	0.1050	0.1050
Capital Required to be Well Capitalized	$ 417,034	$ 408,506
Capital Required to be Well Capitalized to Risk Weighted Assets	0.1000	0.1000
Common Equity Tier 1 Capital
Common Equity Tier 1 Risk Based Capital	$ 549,178	$ 544,331
Common Equity Tier 1 Risk Based Capital to Risk Weighted Assets	0.1317	0.1332
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy	$ 187,665	$ 183,828
Common Equity Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	0.0450	0.0450
Plus Common Equity Tier 1 Risk Based Capital	$ 291,924	$ 285,954
Plus Common Equity Tier 1 Risk Based Capital to Risk Weighted Assets	0.0700	0.0700
Common Equity Tier 1 Risk Based Capital Required to be Well Capitalized	$ 271,072	$ 265,529
Common Equity Tier 1 Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	0.0650	0.0650
Tier 1 Capital
Tier 1 Risk Based Capital	$ 549,178	$ 544,331
Tier 1 Risk Based Capital to Risk Weighted Assets	0.1317	0.1332
Tier 1 Risk Based Capital Required for Capital Adequacy	$ 250,221	$ 245,103
Tier 1 Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	0.0600	0.0600
Plus Tier 1 Risk Based Capital	$ 354,479	$ 347,230
Plus Tier 1 Risk Based Capital to Risk Weighted Assets	0.0850	0.0850
Tier 1 Risk Based Capital Required to be Well Capitalized	$ 333,627	$ 326,804
Tier 1 Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	0.0800	0.0800
Tier 1 Capital
Tier 1 Leverage Capital	$ 549,178	$ 544,331
Tier 1 Leverage Capital to Average Assets	0.0933	0.0941
Tier 1 Leverage Capital Required for Capital Adequacy	$ 235,510	$ 231,334
Tier 1 Leverage Capital Required for Capital Adequacy to Average Assets	0.0400	0.0400
Plus Tier 1 Leverage Capital	$ 235,510	$ 231,334
Plus Tier 1 Leverage Capital to Average Assets	0.0400	0.0400
Tier 1 Leverage Capital Required to be Well Capitalized	$ 294,387	$ 289,167
Tier 1 Leverage Capital Required to be Well Capitalized to Average Assets	0.0500	0.0500

EARNINGS PER COMMON SHARE - Sum

EARNINGS PER COMMON SHARE - Summary of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Earnings Per Share [Abstract]
Net income attributable to shareholders	$ 18,010	$ 3,516
Basic:
Weighted average shares outstanding (in shares)	20,140	20,411
Weighted average shares outstanding (in dollars per share)	$ 0.89	$ 0.17
Diluted:
Dilutive effect of stock option exercises (in shares)	202	279
Total (in shares)	20,342	20,690
Total (in dollars per share)	$ 0.89	$ 0.17

EARNINGS PER COMMON SHARE - Nar

EARNINGS PER COMMON SHARE - Narrative (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0
Employee Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)		81,165