Independent Bank (IBTX) 10-K 25 Feb 22 2021 FY Annual report Financial data

Cover

Cover - USD ($)	12 Months Ended
	Dec. 31, 2021	Feb. 23, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Document Transition Report	false
Entity File Number	001-35854
Entity Registrant Name	Independent Bank Group, Inc.
Entity Incorporation, State or Country Code	TX
Entity Tax Identification Number	13-4219346
Entity Address, Address Line One	7777 Henneman Way
Entity Address, City or Town	McKinney,
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75070-1711
City Area Code	972
Local Phone Number	562-9004
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	IBTX
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 2,769,949,000
Entity Common Stock, Shares Outstanding		42,730,979
Documents Incorporated by Reference	Portions of the Company’s Proxy Statement relating to the 2022 Annual Meeting of Shareholders, which will be filed within 120 days after December 31, 2021, are incorporated by reference into Part III, Items 10 - 14 of this Annual Report on Form 10-K.
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Entity Central Index Key	0001564618
Current Fiscal Year End Date	--12-31

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2021
Audit Information [Abstract]
Auditor Name	RSM US LLP
Auditor Location	Dallas, Texas
Auditor Firm ID	49

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets
Cash and due from banks	$ 243,926	$ 250,485
Interest-bearing deposits in other banks	2,364,518	1,563,502
Cash and cash equivalents	2,608,444	1,813,987
Certificates of deposit held in other banks	3,245	4,482
Securities available for sale, at fair value	2,006,727	1,153,693
Loans held for sale (includes $28,249 and $71,769 carried at fair value, respectively)	32,124	82,647
Loans, net of allowance for credit losses of $148,706 and $87,820, respectively	12,290,740	12,978,238
Premises and equipment, net	308,023	249,467
Other real estate owned	0	475
Federal Home Loan Bank (FHLB) of Dallas stock and other restricted stock	21,573	20,305
Bank-owned life insurance (BOLI)	235,637	220,428
Deferred tax asset	26,178	3,933
Goodwill	994,021	994,021
Other intangible assets, net	75,490	88,070
Other assets	130,446	143,730
Total assets	18,732,648	17,753,476
Deposits:
Noninterest-bearing	5,066,588	4,164,800
Interest-bearing	10,487,320	10,234,127
Total deposits	15,553,908	14,398,927
FHLB advances	150,000	375,000
Other borrowings	283,371	312,175
Junior subordinated debentures	54,221	54,023
Other liabilities	114,498	97,980
Total liabilities	16,155,998	15,238,105
Commitments and contingencies
Stockholders’ equity:
Preferred stock (0 and 0 shares outstanding, respectively)	0	0
Common stock (42,756,234 and 43,137,104 shares outstanding, respectively)	428	431
Additional paid-in capital	1,945,497	1,934,807
Retained earnings	625,484	543,800
Accumulated other comprehensive income	5,241	36,333
Total stockholders’ equity	2,576,650	2,515,371
Total liabilities and stockholders’ equity	$ 18,732,648	$ 17,753,476

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Loans held for sale, fair value option	$ 28,249	$ 71,769
Allowance for Credit Losses	$ 148,706	$ 87,820
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets	Other assets
Operating lease, liability, statement of financial position	Other liabilities	Other liabilities
Preferred stock, shares outstanding (shares)	0	0
Common stock, shares outstanding (shares)	42,756,234	43,137,104

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Interest income:
Interest and fees on loans	$ 547,931	$ 579,085	$ 611,589
Interest on taxable securities	22,754	19,150	21,324
Interest on nontaxable securities	8,344	8,472	8,482
Interest on interest-bearing deposits and other	4,533	4,799	11,537
Total interest income	583,562	611,506	652,932
Interest expense:
Interest on deposits	44,199	76,266	123,384
Interest on FHLB advances	2,038	4,170	10,173
Interest on other borrowings	15,247	12,462	11,590
Interest on junior subordinated debentures	1,756	2,162	3,028
Total interest expense	63,240	95,060	148,175
Net interest income	520,322	516,446	504,757
Provision for credit losses	(9,000)	42,993	14,805
Net interest income after provision for credit losses	529,322	473,453	489,952
Noninterest income:
Service charges on deposit accounts	9,842	9,303	12,145
Investment management fees	8,586	7,546	9,330
Mortgage banking revenue	23,157	36,491	15,461
Mortgage warehouse purchase program fees	6,908	6,088	3,287
Gain on sale of loans	56	356	6,779
Gain on sale of branches	0	0	1,549
Gain on sale of trust business	0	0	1,319
Gain (loss) on sale of other real estate	63	(36)	875
Gain on sale of securities available for sale	13	382	275
(Loss) gain on sale and disposal of premises and equipment	(304)	370	(585)
Increase in cash surrender value of BOLI	5,209	5,347	5,525
Other	12,987	19,216	22,216
Total noninterest income	66,517	85,063	78,176
Noninterest expense:
Salaries and employee benefits	180,336	157,540	162,683
Occupancy	40,688	39,210	37,654
Communications and technology	22,355	23,113	22,248
FDIC assessment	5,865	6,912	1,065
Advertising and public relations	1,097	2,416	2,527
Other real estate owned expenses, net	4	487	418
Impairment of other real estate	0	784	1,801
Amortization of other intangible assets	12,580	12,671	12,880
Professional fees	15,530	12,630	7,936
Acquisition expense, including legal	0	16,225	33,445
Other	35,151	34,146	39,207
Total noninterest expense	313,606	306,134	321,864
Income before taxes	282,233	252,382	246,264
Income tax expense	57,483	51,173	53,528
Net income	$ 224,750	$ 201,209	$ 192,736
Basic earnings per share (usd per share)	$ 5.22	$ 4.67	$ 4.46
Diluted earnings per share (usd per share)	$ 5.21	$ 4.67	$ 4.46

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 224,750	$ 201,209	$ 192,736
Other comprehensive (loss) income:
Unrealized (losses) gains arising during the period	(38,292)	21,540	35,620
Tax effect	(8,041)	4,210	7,790
Unrealized (losses) gains arising during the period, net of taxes	(30,251)	17,330	27,830
Reclassification of amount of gains realized through sale of securities	(13)	(382)	(275)
Tax effect	(3)	(75)	(60)
Reclassification of amount of gains realized through sale of securities, net of tax	(10)	(307)	(215)
Change in unrealized (losses) gains on securities, net of tax	(30,261)	17,023	27,615
Unrealized holding losses arising during the period	(455)	0	0
Tax effect	(96)	0	0
Unrealized losses arising during the period, net of tax	(359)	0	0
Reclassification of amount of gains recognized into income	(597)	0	0
Tax effect	(125)	0	0
Reclassification of amount of gains recognized into income, net of tax	(472)	0	0
Change in unrealized losses on derivative financial instruments	(831)	0	0
Total other comprehensive (loss) income	(31,092)	17,023	27,615
Comprehensive income	$ 193,658	$ 218,232	$ 220,351

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock $0.01 Par Value 10 million shares authorized	Common Stock $0.01 Par Value 100 million shares authorized	Additional Paid in Capital	Retained Earnings	Accumulated Other Comprehensive (Loss) Income	Cumulative effect of change in accounting principle	Cumulative effect of change in accounting principleRetained Earnings	Cumulative effect of change in accounting principleAccumulated Other Comprehensive (Loss) Income	Cumulative effect, period of adoption, adjusted balance	Cumulative effect, period of adoption, adjusted balancePreferred Stock $0.01 Par Value 10 million shares authorized	Cumulative effect, period of adoption, adjusted balanceCommon Stock $0.01 Par Value 100 million shares authorized	Cumulative effect, period of adoption, adjusted balanceAdditional Paid in Capital	Cumulative effect, period of adoption, adjusted balanceRetained Earnings	Cumulative effect, period of adoption, adjusted balanceAccumulated Other Comprehensive (Loss) Income
Beginning balance (in shares) at Dec. 31, 2018			30,600,582									30,600,582
Beginning balance at Dec. 31, 2018	$ 1,606,433	$ 0	$ 306	$ 1,317,616	$ 296,816	$ (8,305)	$ (926)	$ (926)	$ 0	$ 1,605,507	$ 0	$ 306	$ 1,317,616	$ 295,890	$ (8,305)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	192,736				192,736
Other comprehensive income (loss), net of tax	27,615					27,615
Stock issued for acquisition of bank, net of offering costs (in shares)			13,179,748
Stock issued for acquisition of bank, net of offering costs of $804 as of December 31, 2019	601,068		$ 132	600,936
Common stock repurchased (shares)			(952,844)
Common stock repurchased	(51,659)		$ (9)		(51,650)
Restricted stock forfeited (in shares)			(15,866)
Restricted stock forfeited	0
Restricted stock granted (in shares)			138,608
Restricted stock granted	0		$ 1	(1)
Stock based compensation expense	7,808			7,808
Cash dividends ($1.00, $1.05 and $1.32 per share as of December 31, 2019, 2020 and 2021, respectively)	(43,302)				(43,302)
Ending balance (in shares) at Dec. 31, 2019			42,950,228
Ending balance at Dec. 31, 2019	2,339,773	0	$ 430	1,926,359	393,674	19,310
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	201,209				201,209
Other comprehensive income (loss), net of tax	17,023					17,023
Common stock repurchased (shares)			(112,499)
Common stock repurchased	(5,819)		$ (1)		(5,818)
Restricted stock forfeited (in shares)			(10,915)
Restricted stock forfeited	0		$ 0
Restricted stock granted (in shares)			310,290
Restricted stock granted	0		$ 2	(2)
Stock based compensation expense	8,450			8,450
Cash dividends ($1.00, $1.05 and $1.32 per share as of December 31, 2019, 2020 and 2021, respectively)	(45,265)				(45,265)
Ending balance (in shares) at Dec. 31, 2020			43,137,104									43,137,104
Ending balance at Dec. 31, 2020	2,515,371	0	$ 431	1,934,807	543,800	36,333	$ (53,880)	$ (53,880)		$ 2,461,491	$ 0	$ 431	$ 1,934,807	$ 489,920	$ 36,333
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	224,750				224,750
Other comprehensive income (loss), net of tax	(31,092)					(31,092)
Common stock repurchased (shares)			(461,068)
Common stock repurchased	(32,132)		$ (4)		(32,128)
Restricted stock forfeited (in shares)			(35,265)
Restricted stock forfeited	0
Restricted stock granted (in shares)			115,463
Restricted stock granted	0		$ 1	(1)
Stock based compensation expense	10,691			10,691
Cash dividends ($1.00, $1.05 and $1.32 per share as of December 31, 2019, 2020 and 2021, respectively)	(57,058)				(57,058)
Ending balance (in shares) at Dec. 31, 2021			42,756,234
Ending balance at Dec. 31, 2021	$ 2,576,650	$ 0	$ 428	$ 1,945,497	$ 625,484	$ 5,241

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Stock issued for acquisition of bank, net of offering costs			$ 804
Cash dividends paid (usd per share)	$ 1.32	$ 1.05	$ 1
Preferred stock par value (in usd per share)	$ 0.01	$ 0.01	$ 0.01	$ 0.01
Preferred stock shares authorized (shares)	10,000,000	10,000,000	10,000,000	10,000,000
Common stock, par value (usd per share)	$ 0.01	$ 0.01	$ 0.01	$ 0.01
Common stock shares authorized (shares)	100,000,000	100,000,000	100,000,000	100,000,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income	$ 224,750	$ 201,209	$ 192,736
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation expense	12,385	12,728	11,783
Accretion income recognized on acquired loans	(21,174)	(30,378)	(46,071)
Amortization of other intangibles assets	12,580	12,671	12,880
Amortization of premium on securities, net	5,226	2,892	2,671
Amortization of discount and origination costs on borrowings	894	720	633
Stock based compensation expense	10,691	8,450	7,808
Excess tax (benefit) expense on restricted stock vested	(691)	243	21
FHLB stock dividends	(128)	(567)	(854)
Loss (gain) on sale and disposal of premises and equipment	304	(370)	585
Gain on sale of loans	(56)	(356)	(6,779)
Gain on sale of branch	0	0	(1,549)
Gain on sale of trust business	0	0	(1,319)
Gain on sale of securities available for sale	(13)	(382)	(275)
(Gain) loss on sale of other real estate owned	(63)	36	(875)
Impairment of other real estate	0	784	1,801
Impairment of other assets	124	462	1,173
Deferred tax expense (benefit)	5,353	(1,633)	14,102
Provision for credit losses	(9,000)	42,993	14,805
Increase in cash surrender value of BOLI	(5,209)	(5,347)	(5,525)
Net gain on mortgage loans held for sale	(21,799)	(38,175)	(15,133)
Originations of loans held for sale	(659,536)	(901,163)	(435,076)
Proceeds from sale of loans held for sale	731,858	892,336	447,291
Net change in other assets	14,293	(35,025)	(5,878)
Net change in other liabilities	(23,356)	(7,833)	(15,636)
Net cash provided by operating activities	277,433	154,295	173,319
Cash flows from investing activities:
Proceeds from maturities, calls and paydowns of securities available for sale	7,403,109	5,507,844	5,400,634
Proceeds from sale of securities available for sale	9,294	13,862	192,417
Purchases of securities available for sale	(8,308,955)	(5,570,815)	(5,390,543)
Purchases of certificates of deposit held in other banks	0	0	(5,705)
Proceeds from maturities of certificates of deposit held in other banks	1,237	1,237	1,473
Proceeds from surrender of bank owned life insurance contracts	0	0	802
Purchase of bank owned life insurance contracts	(10,000)	0	0
Purchases of FHLB stock and other restricted stock	(1,190)	(27,037)	(9,397)
Proceeds from redemptions of FHLB stock and other restricted stock	50	37,351	34,863
Proceeds from sale of loans	3,034	19,181	90,025
Net loans originated held for investment	14,805	(674,142)	(469,023)
Originations of mortgage warehouse purchase loans	(30,418,842)	(25,833,339)	(12,835,522)
Proceeds from pay-offs of mortgage warehouse purchase loans	31,083,791	25,066,859	12,318,495
Additions to premises and equipment	(71,356)	(21,135)	(31,680)
Proceeds from sale of premises and equipment	21	2,022	2,100
Proceeds from sale of other real estate owned	538	6,724	8,207
Cash acquired in connection with acquisition	0	0	39,913
Cash paid in connection with acquisition	0	0	(9)
Selling costs paid in connection with branch sale	0	0	(144)
Net cash transferred in branch sale	0	0	(25,163)
Proceeds from sale of trust business	0	0	4,269
Net cash used in investing activities	(294,464)	(1,471,388)	(673,988)
Cash flows from financing activities:
Net increase in demand deposits, money market and savings accounts	1,508,335	2,871,869	876,842
Net (decrease) increase in time deposits	(353,354)	(414,278)	237,136
Repayments of FHLB advances	(225,000)	(1,550,000)	(1,807,653)
Proceeds from FHLB advances	0	1,600,000	1,700,000
Proceeds from other borrowings	75,000	156,489	65,000
Repayments of other borrowings	(104,500)	(47,086)	(40,500)
Offering costs paid in connection with acquired bank	0	0	(804)
Repurchase of common stock	(32,132)	(5,819)	(51,659)
Dividends paid	(56,861)	(45,265)	(43,302)
Net cash (used in) provided by financing activities	811,488	2,565,910	935,060
Net change in cash and cash equivalents	794,457	1,248,817	434,391
Cash and cash equivalents at beginning of period	1,813,987	565,170	130,779
Cash and cash equivalents at end of period	$ 2,608,444	$ 1,813,987	$ 565,170

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Nature of operations: Independent Bank Group, Inc. (IBG) through its subsidiary, Independent Bank, a Texas state banking corporation, doing business as Independent Financial (Bank) (collectively known as the Company), provides a full range of banking services to individual and corporate customers in the North, Central and Southeast, Texas areas and along the Colorado Front Range, through its various branch locations in those areas. The Company is engaged in traditional community banking activities, which include commercial and retail lending, deposit gathering, and investment and liquidity management activities. The Company’s primary deposit products are demand deposits, money market accounts and certificates of deposit, and its primary lending products are commercial business and real estate, real estate mortgage and consumer loans. Basis of presentation: The accompanying consolidated financial statements include the accounts of IBG and all other entities in which IBG has controlling financial interest. All material intercompany transactions and balances have been eliminated in consolidation. In addition, the Company wholly-owns nine statutory business trusts that were formed for the purpose of issuing trust preferred securities and do not meet the criteria for consolidation (See Note 11. Junior Subordinated Debentures ). Accounting standards codification: The Financial Accounting Standards Board's (FASB) Accounting Standards Codification (ASC) is the officially recognized source of authoritative U.S. generally accepted accounting principles (GAAP) applicable to all public and non-public non-governmental entities. Rules and interpretive releases of the SEC under the authority of federal securities laws are also sources of authoritative GAAP for SEC registrants. All other accounting literature is considered non-authoritative. Segment reporting: The Company has one reportable segment. The Company’s chief operating decision-maker uses consolidated results to make operating and strategic decisions. Reclassifications: Certain prior period financial statement and disclosure amounts have been reclassified to conform to current period presentation. The reclassifications have no effect on net income or stockholders' equity as previously reported. Use of estimates: The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect certain reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Accordingly, actual results could differ from those estimates. The material estimates included in the financial statements relate to the allowance for credit losses, the valuation of goodwill and valuation of assets and liabilities acquired in business combinations. Cash and cash equivalents: For the purposes of reporting cash flows, cash and cash equivalents include cash on hand, amounts due from banks and federal funds sold. All highly liquid investments with an initial maturity of less than ninety days are considered to be cash equivalents. The Company maintains deposits with other financial institutions in amounts that exceed FDIC insurance coverage. The Company's management monitors the balance in these accounts and periodically assesses the financial condition of the other financial institutions. The Company has not experienced any losses in such accounts and believes it is not exposed to any significant credit risks on cash or cash equivalents. Restricted cash: The Company maintains cash collateral balances which have been pledged to derivative counterparties and are legally restricted as to use. Certificates of deposit: Certificates of deposit are FDIC insured deposits in other financial institutions that mature within 18 months and are carried at cost. Securities: Debt securities that management has the positive intent and ability to hold to maturity are classified as held to maturity and recorded at amortized cost. Debt securities that the Company intends to hold for an indefinite period of time, but not necessarily to maturity are classified as available for sale. Securities available for sale are reported at fair value with unrealized gains or losses reported as a separate component of other comprehensive income, net of tax. Any decision to sell a security classified as available for sale would be based on various factors, including significant movements in interest rates, changes in the maturity mix of the Company's assets and liabilities, liquidity needs, regulatory capital considerations and other similar factors. The amortization of premiums and accretion of discounts, computed by the interest method generally over their contractual lives, are recognized in interest income. Premiums on callable securities are amortized to their earliest call date. Realized gains or losses, determined on the basis of the cost of specific securities sold, are included in earnings on the trade date. As of December 31, 2021 and 2020, all of the Company's securities were classified as available for sale. Loans held for sale: The Company originates residential mortgage loans that may subsequently be sold to unaffiliated third parties. The Company elected the fair value option for certain residential mortgage loans held for sale in accordance with ASC 825, Financial Instruments. This election allows for a more effective offset of the changes in fair values of the loans and the derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting under ASC 815, Derivatives and Hedging . The Company has not elected the fair value option for other residential mortgage loans held for sale primarily because they are not economically hedged using derivative instruments. Mortgage loans originated and intended for sale not recorded under the fair value option are carried at the lower of aggregate cost or fair value, as determined by aggregate outstanding commitments from investors. Net unrealized losses, if any, are recognized through a valuation allowance by charges to income. All mortgage loans held for sale are sold without servicing rights retained. Gains and losses on sales of loans are recognized in noninterest income at settlement dates and are determined by the difference between the sales proceeds and the carrying value of the loans. Loans held for investment: Loans that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off are reported at their outstanding principal balance, net of unearned interest, purchase premiums and discounts, deferred loan fees or costs and an allowance for credit losses. Loan origination fees, net of direct origination costs, are deferred and recognized as an adjustment to the related loan yield using the effective interest method without anticipating prepayments. Further information regarding the Company's accounting policies related to past due loans, non-accrual loans, collateral dependent loans and troubled-debt restructurings is presented in Note 5. Loans, Net and Allowance for Credit Losses on Loans . Acquired loans: In accordance with ASC 326, Measurement of Credit Losses on Financial Instruments , loans acquired in connection with a business combination are recorded at their acquisition-date fair value. The allowance for credit losses related to the acquired loan portfolio is not carried over. Acquired loans are classified into two categories based on the credit risk characteristics of the underlying borrowers as either purchased credit deteriorated (PCD) loans, or loans with no evidence of credit deterioration (non-PCD). PCD loans are defined as a loan or pool of loans that have experienced more-than-insignificant credit deterioration since the origination date. For PCD loans, an initial allowance is established on the acquisition date using the same methodology as other loans held for investment and combined with the fair value of the loan to arrive at acquisition date amortized cost. Accordingly, no provision for credit losses is recognized on PCD loans at the acquisition date. Subsequent to the acquisition date, changes to the allowance are recognized in the provision for credit losses. Non-PCD loans are pooled into segments together with originated held for investment loans that share similar risk characteristics and have an allowance established on the acquisition date, which is recognized in the current period provision for credit losses. Determining the fair value of the acquired loans involves estimating the principal and interest payment cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. For PCD loans, the non-credit discount or premium is allocated to individual loans as determined by the difference between the loan’s unpaid principal balance and amortized cost basis. The non-credit premium or discount is recognized into interest income on a level yield basis over the remaining expected life of the loan. For non-PCD loans, the fair value discount or premium is allocated to individual loans and recognized into interest income on a level yield basis over the remaining expected life of the loan. Prior to January 1, 2021 as further discussed in Note 2. Recent Accounting Standards , loans acquired in a business combination that had evidence of credit impairment and for which it was probable, at acquisition, that the Company would be unable to collect all contractually required payments receivable were considered PCI. PCI loans were accounted for individually or aggregated into pools of loans based on common risk characteristics such as credit grade, loan type, and date of origination. Allowance for credit losses: Refer to Note 2. Recent Accounting Standards for discussion of the change in methodology used to calculate the allowance for credit losses as a result of adopting of ASU 2016-13, Financial Instruments - Credit Losses (Topic 326), effective January 1, 2021. Allowance for credit losses - loans : In accordance with ASC 326, Measurement of Credit Losses on Financial Instruments , the allowance for credit losses on loans is a valuation account that is deducted from the amortized cost basis of loans to present management's best estimate of the net amount expected to be collected. Loans, or portions thereof, are charged-off against the allowance for credit losses when management believes that collectability of the principal is unlikely. Subsequent recoveries, if any, are credited to the allowance. The allowance is increased (decreased) by provisions (or reversals of) reported in the income statement as a component of provision for credit losses. Management has made the accounting policy election to exclude accrued interest receivable on loans from the estimate of credit losses and reports accrued interest separately in other assets in the consolidated balance sheets. Further information regarding Company policies and methodology used to estimate the allowance for credit losses on loans is presented in Note 5. Loans, Net and Allowance for Credit Losses on Loans . Prior to 2021, as further discussed in Note 2. Recent Accounting Standards , the allowance for credit losses on loans was a valuation account established through a provision for credit losses charged to expense, which represented management’s best estimate of inherent losses that had been incurred within the existing portfolio of loans. The allowance for credit losses on loans included allowance allocations calculated in accordance with ASC Topic 310, Receivables , and allowance allocations calculated in accordance with ASC Topic 450, Contingencies . Allowance for credit losses - available for sale securities: For available for sale securities in an unrealized loss position, the Company first assesses whether it intends to sell or it is more-likely-than-not that it will be required to sell the securities before recovery of the amortized cost basis. If either of these criteria is met, the securities amortized cost basis is written down to fair value as a current period expense. If either of the above criteria is not met, the Company evaluates whether the decline in fair value is the result of credit losses or other factors. In making this assessment, management may consider various factors including the extent to which fair value is less than amortized cost, performance of any underlying collateral and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected are compared to the amortized cost basis of the security and any excess of the amortized cost basis over the present value of expected cash flows is recorded as an allowance for credit loss, limited to the amount by which the fair value is less than the amortized cost basis. Any impairment not recorded through an allowance for credit loss is recognized in other comprehensive income as a non credit-related impairment. Changes in the allowance for credit losses are recorded as provision for (or reversal of) credit losses. Available for sale securities are charged-off against the allowance or, in the absence of any allowance, written down through income when deemed uncollectible by management or when either of the aforementioned criteria regarding intent or requirement to sell is met. Allowance for credit losses - held to maturity securities : The allowance for credit losses on held to maturity securities is a valuation account that is deducted from the amortized cost basis of held to maturity securities to present management's best estimate of the net amount expected to be collected. Held to maturity securities are charged-off against the allowance when deemed uncollectible by management. Adjustments to the allowance are reported in the income statement as a component of provision for credit losses. Management measures expected credit losses on held to maturity securities on a collective basis by major security type with each type sharing similar risk characteristics and considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. Management has made the accounting policy election to exclude accrued interest receivable on available for sale and held to maturity securities from the estimate of credit losses and report accrued interest separately in other assets in the consolidated balance sheet. Allowance for credit losses on off-balance sheet credit exposures: The allowance for credit losses on off-balance sheet credit exposures is a liability account, calculated in accordance with ASC 326, representing expected credit losses over the contractual period for which the Company is exposed to credit risk resulting from a contractual obligation to extend credit. No allowance is recognized if we have the unconditional right to cancel the obligation. The allowance is reported as a component of other liabilities in the consolidated balance sheets. Adjustments to the allowance are reported in the income statement as a component of provision for credit losses. Further information regarding Company policies and methodology used to estimate the allowance for credit losses on off-balance sheet credit exposures is presented in Note 14. Off-Balance Sheet Arrangements, Commitments and Contingencies . Premises and equipment, net: Land is carried at cost. Bank premises, furniture and equipment and aircraft are carried at cost, less accumulated depreciation computed principally by the straight-line method over the estimated useful lives of the assets, which range from three Leasehold improvements are carried at cost and are depreciated over the shorter of the estimated useful life or the lease period. Software: Costs incurred in connection with development or purchase of internal use software and cloud computing arrangements, including in-substance software licenses, are capitalized. Amortization is computed on a straight-line basis over the estimated useful life of the asset, which generally ranges from one Leases: The Company's leases are accounted for under ASC Topic 842, Leases . For operating leases with a term greater than one year, the Company recognizes operating right-of-use (ROU) lease assets and operating lease liabilities, which are recorded in other assets and other liabilities, respectively, in the consolidated balance sheets. The Company determines if an arrangement is a lease at inception. Operating ROU lease assets and related liabilities are recognized at commencement date based on the present value of lease payments over the lease term. As the Company's leases do not provide an implicit rate, the Company uses its incremental borrowing rate referenced to the Federal Home Loan Bank Secure Connect advance rates for borrowings of similar terms in determining the present value of lease payments. The operating ROU lease asset also includes any lease pre-payments made and excludes lease incentives. The Company's lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term. The Company has lease agreements with lease and non-lease components, which the Company has elected to account for separately as the non-lease component amounts are readily determinable under most leases. Long-term assets: Premises and equipment and other long-term assets are reviewed for impairment when events indicate that their carrying amount may not be recoverable from future undiscounted cash flows. If impaired, the assets are recorded at fair value. Other real estate owned: Real estate properties acquired through, or in lieu of, loan foreclosure are initially recorded at fair value less estimated selling costs at the date of foreclosure, establishing a new cost basis. After foreclosure, valuations are periodically performed by management and the real estate is carried at the lower of carrying amount or fair value less cost to sell. Revenue and expenses from operations of other real estate owned and impairment charges on other real estate are included in noninterest expense. Gains and losses on sale of other real estate are included in noninterest income. Goodwill and other intangible assets, net: Goodwill represents the excess of costs over fair value of net assets of businesses acquired. Goodwill is tested for impairment annually on December 31 or on an interim basis if an event triggering impairment may have occurred. On January 1, 2020, ASU 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment became effective for the Company as further explained in Note 2. Recent Accounting Standards . Under the guidance, if a reporting unit’s carrying amount exceeds its fair value, an entity will record an impairment charge based on that difference. As of December 31, 2021, the fair value of the Company’s stock price and calculated market capitalization exceeded its carrying value. Core deposit intangibles and other acquired customer relationship intangibles arising from bank acquisitions are amortized on a straight-line basis over their estimated useful lives of ten years and thirteen years, respectively. Other intangible assets are tested for impairment whenever events or changes in circumstances indicate the carrying amount of the assets may not be recoverable from future undiscounted cash flows. Restricted stock : The Bank is a member of the FHLB system. Members are required to own a certain amount of stock based on the level of borrowings and other factors, and may invest in additional amounts. FHLB of Dallas and other restricted stock do not have readily determinable fair values as ownership is restricted and they lack a ready market. As a result, these stocks are carried at cost and evaluated periodically by management for impairment. Both cash and stock dividends are reported as income. Bank-owned life insurance: Bank-owned life insurance is recorded at the amount that can be realized under the insurance contracts at the balance sheet date, which is the cash surrender value adjusted for other charges or other amounts due that are probable at settlement. Changes in the net cash surrender value of the policies, as well as insurance proceeds received are reflected in noninterest income. Income taxes: Income tax expense is the total of the current year income tax due or refundable and the change in deferred tax assets and liabilities (excluding deferred tax assets and liabilities related to business combinations or components of other comprehensive income). Deferred tax assets and liabilities are the expected future tax amounts for the temporary differences between carrying amounts and tax bases of assets and liabilities, computed using enacted tax rates. The effect of a change in tax rates on deferred assets and liabilities is recognized in income taxes during the period that includes the enactment date. A valuation allowance, if needed, reduces deferred tax assets to the expected amount more likely than not to be realized. Realization of deferred tax assets is dependent upon the level of historical income, prudent and feasible tax planning strategies, reversals of deferred tax liabilities and estimates of future taxable income. The Company evaluates uncertain tax positions at the end of each reporting period. The Company may recognize the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefit recognized in the financial statements from any such position is measured based on the largest benefit that has a greater than fifty percent likelihood of being realized upon ultimate settlement. For tax positions not meeting the "more likely than not" test, no tax benefit is recorded. Any interest and/or penalties related to income taxes are reported as a component of income tax expense. Loan commitments and related financial instruments: In the ordinary course of business, the Company has entered into certain off-balance sheet financial instruments consisting of commitments to extend credit, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded in the financial statements when they are funded or related fees are incurred or received. Stock based compensation: Compensation cost is recognized for restricted stock awards/stock units issued to employees based on the market price of the Company's common stock on the grant date. Stock-based compensation expense is generally recognized using the straight-line method over the requisite service period for time-based awards. Compensation expense for performance stock units is recognized over the service period of the award based upon the probable number of units expected to vest. The impact of forfeitures of stock-based payment awards on compensation expense is recognized as forfeitures occur. Transfers of financial assets: Transfers of financial assets are accounted for as sales, when control over the assets has been relinquished. Control over transferred assets is deemed to be surrendered when the assets have been isolated from the Company, the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity. Advertising costs: Advertising costs are expensed as incurred. Business combinations: The Company applies the acquisition method of accounting for business combinations. Under the acquisition method, the acquiring entity in a business combination recognizes 100% of the assets acquired and liabilities assumed at their acquisition date fair values. Management utilizes valuation techniques appropriate for the asset or liability being measured in determining these fair values. Any excess of the purchase price over amounts allocated to assets acquired, including identifiable intangible assets, and liabilities assumed is recorded as goodwill. Where amounts allocated to assets acquired and liabilities assumed is greater than the purchase price, a bargain purchase gain is recognized. Adjustments identified during the measurement period are recognized in the reporting period in which the adjustment amounts are determined. Acquisition-related costs are expensed as incurred. Comprehensive income: Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income. Although certain changes in assets and liabilities, such as unrealized gains and losses on available for sale securities, are reported as a separate component of the equity section of the balance sheet, such items, along with net income, are components of comprehensive income. Gains and losses on available for sale securities are reclassified to net income as the gains or losses are realized upon sale of the securities. For cash flow hedges, gains and losses on the derivative(s) are recorded in accumulated other comprehensive income and subsequently reclassified into interest income in the same period that the hedged transaction affects earnings. Fair values of financial instruments: Accounting standards define fair value, establish a framework for measuring fair value in GAAP, and require certain disclosures about fair value measurements (see Note 17. Fair Value Measurements ). In general, fair values of financial instruments are based upon quoted market prices, where available. If such quoted market prices are not available, fair value is based upon models that primarily use, as inputs, observable market-based parameters. Valuation adjustments may be made to ensure that financial instruments are recorded at fair value. These adjustments may include amounts to reflect counterparty credit quality and the Company's creditworthiness, among other things, as well as unobservable parameters. Any such valuation adjustments are applied consistently over time. Derivative financial instruments: The Company enters into certain derivative financial instruments: interest rate lock commitments, forward mortgage-backed securities trades and interest rate swaps. The accounting for changes in fair value depends on the intended use of the derivative. Changes in fair value of derivatives designated in a qualifying hedge relationship are recorded in accumulated other comprehensive income. Changes in fair value of derivatives not designated in a qualifying hedge relationship are recognized directly in earnings. All derivatives are carried at fair value in either other assets or other liabilities. See Note 18. Derivative Financial Instruments for further information regarding Company policy. Mortgage banking: This revenue category reflects the Company's mortgage production revenue, including fees and income derived from mortgages originated with the intent to sell, gains on sales of mortgage loans and the initial and subsequent changes in the fair value of the mortgage derivatives. Interest earned on mortgage loans is recorded in interest income. Revenue recognition: ASC Topic 606, R evenue from Contracts with Customers (ASC 606) , establishes principles for reporting information about the nature, amount, timing and uncertainty of revenue and cash flows arising from the entity's contracts to provide goods or services to customers. The core principle requires an entity to recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration that it expects to be entitled to receive in exchange for those goods or services recognized as performance obligations are satisfied. The majority of the Company's revenue-generating transactions are not subject to ASC 606, including revenue generated from financial instruments, such as loans, letters of credit, and investment securities, as well as revenue related to mortgage banking activities, and BOLI, as these activities are subject to other accounting guidance. Descriptions of revenue-generating activities that are within the scope of ASC 606, and are presented in the accompanying Consolidated Statements of Income as components of noninterest income, are as follows: • Service charges on deposit accounts - these represent general service fees for monthly account maintenance and activity or transaction-based fees and consist of transaction-based revenue, time-based revenue (service period), item-based revenue or some other individual attribute-based revenue. Revenue is recognized when the performance obligation is completed which is generally monthly for account maintenance services or when a transaction has been completed (such as a wire transfer). Payment for such performance obligations are generally received at the time the performance obligations are satisfied. • Investment management and trust - includes income related to providing investment management and trust services to customers under investment management and trust contracts. Also included are fees received from a third party broker-dealer as part of a revenue-sharing agreement for fees earned from customers that are referred to a third party. The investment management fees and referral fees are billed and paid on a quarterly basis and recognized ratably throughout the quarter as performance obligations are satisfied. • Mortgage warehouse purchase program fees - includes fees for the administration and funding of mortgage loans, as well as renewal and application fees received from mortgage originator customers through our mortgage warehouse purchase program. Revenue related to the warehouse program is recognized when the related loan interest is paid off or upon renewal or application. • Gains/losses on the sale of other real estate owned - generally recognized when the performance obligation is complete which is typically at delivery of control over the property to the buyer at time of each real estate closing. • Other noninterest income - includes the Company's correspondent bank earnings credit, acquired loan recoveries, other deposit fees, and merchant interchange income. The majority of these fees in other noninterest income are not subject to the requirements of ASC 606. The other deposit fees and merchant interchange income are in the scope of ASC 606, and payment for such performance obligations are generally received at the time the performance obligations are satisfied. The Company has made no significant judgments in applying the revenue guidance prescribed in ASC 606 that affect the determination of the amount and timing of revenue from the above-described contracts with customers. Subsequent events: Companies are required to evaluate events and transactions that occur after the balance sheet date but before the date the financial statements are issued. They must recognize in the financial statements the effect of all events or transactions that provide additional evidence of conditions that existed at the balance sheet date, including the estimates inherent in the financial statement preparation process. Entities shall not recognize the impact of events or transactions that provide evidence about conditions that did not exist at the balance sheet date but arose after that date. The Company has evaluated subsequent events through the date of filing these financial statements with the Securities and Exchange Commission (SEC) and noted no subsequent events requiring financial statement recognition or disclosure, except as disclosed in Note 22. Subsequent Events . Earnings per share: Basic earnings per common share is calculated as net income available to common shareholders divided by the weighted average number of common shares outstanding during the period. The unvested share-based payment awards that contain rights to nonforfeitable dividends are considered participating securities for this calculation. Diluted earnings per common share includes the dilutive effect of additional potential common shares issuable under participating nonvested restricted stock awards as well as performance stock units (PSUs). The participating nonvested restricted stock awards were not included in dilutive shares as

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Standards Adoption of new accounting standards ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) (ASC 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13). On January 1, 2020, ASU 2016-13, as amended, became effective for the Company. ASU 2016-13 replaces the incurred loss methodology with an expected loss methodology that is referred to as the current expected credit loss (CECL) methodology. The measurement of expected credit losses under the CECL methodology is applicable to financial assets measured at amortized cost, including loan receivables and held to maturity debt securities. It also applies to off-balance sheet credit exposures not accounted for as insurance (loan commitments, standby letters of credit, financial guarantees, and other similar instruments). The CECL model requires the measurement of all expected credit losses on applicable financial assets based on historical experience, current conditions, and reasonable and supportable forecasts. In addition, ASU 2016-13 includes certain changes to the accounting for available for sale securities such as requiring credit-related impairments to be recognized as an allowance for credit losses rather than as a direct write-down of the securities amortized cost basis when management does not intend to sell or believes that it is more likely than not they will be required to sell securities prior to recovery of the securities amortized cost basis. On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (CARES Act) was signed by the President of the United States that included an option for financial institutions to delay the implementation of ASU 2016-13 until the earlier of the termination date of the national emergency declaration by the President or December 31, 2020. On December 27, 2020, the Consolidated Appropriations Act, 2021 (Act 2021), was signed into law which further extended the implementation date of CECL to the earlier of the first day of the entity’s fiscal year that begins after the date on which the COVID-19 national emergency terminates or January 1, 2022. Under the CARES Act provision, the Company elected to delay implementation of ASU 2016-13 and calculated and recorded its provision for credit losses under the incurred loss model that existed prior to ASU 2016-13 for the year ended December 31, 2020. With regard to Act 2021 amendments, the SEC staff indicated it would not object to a registrant early adopting on December 31, 2020, retrospective to January 1, 2020, or January 1, 2021, effective as of January 1, 2021. Under this guidance, the Company elected to adopt ASU 2016-13 with an effective implementation date of January 1, 2021. The Company adopted ASU 2016-13 using the modified retrospective method for all financial assets measured at amortized cost and off-balance sheet credit exposures. As a result of this adoption, the Company recognized a cumulative effect reduction to retained earnings totaling $53,880, net of a recorded deferred tax asset of $15,113, and reclassed $13,035 of allowance for credit loss related to financial assets purchased with credit deterioration (PCD) that were previously classified as purchased credit impaired (PCI) and accounted for under ASC 310-30 as discussed below. Results for periods beginning after January 1, 2021 are presented in accordance with ASU 2016-13 while prior period amounts continue to be reported in accordance with previously applicable GAAP. The Company adopted ASU 2016-13 using the prospective transition approach for PCD assets. In accordance with the standard, management did not reassess whether PCI assets met the criteria of PCD assets as of the date of adoption. On January 1, 2021, the amortized cost basis of the PCD assets were adjusted to reflect the addition of the allowance for credit losses. The remaining noncredit discount (based on the adjusted amortized cost basis) was accreted into interest income at the effective interest rate as of January 1, 2021. The following table illustrates the impact of ASU 2016-13 on the allowances for credit losses as of January 1, 2021, the date of adoption: January 1, 2021 Pre-Adoption Allowance Impact of Adoption Initial allowance on loans purchased with credit deterioration Post-Adoption Allowance Assets: Allowance for credit losses on Loans: Commercial $ 27,311 $ 12,775 $ 4,328 $ 44,414 Commercial real estate 36,698 29,108 7,640 73,446 Commercial construction, land and land development 13,425 22,008 927 36,360 Residential real estate 6,786 (2,255) 140 4,671 Single-family interim construction 2,156 7,179 — 9,335 Agricultural 337 (178) — 159 Consumer 684 (334) — 350 Unallocated 423 (423) — — $ 87,820 $ 67,880 $ 13,035 $ 168,735 Liabilities: Allowance for credit losses on off-balance sheet credit exposures $ — $ 1,113 $ — $ 1,113 ASU 2020-08, Codification Improvements to Subtopic 310-20, Receivables - Nonrefundable Fees and Other Costs . ASU 2020-08 clarifies the accounting for the amortization of purchase premiums for callable debt securities with multiple call dates. ASU 2020-8 was effective for the Company on January 1, 2021 and did not have a significant impact on our financial statements. ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting and subsequent clarifying update ASU 2021-01 Reference Rate Reform (Topic 848); Scope. ASU 2020-04 provides temporary optional guidance to ease the potential burden in accounting for reference rate reform. The new guidance provides optional expedients and exceptions for applying GAAP to contract modifications and hedging relationships, subject to meeting certain criteria, that reference LIBOR or another reference rate expected to be discontinued. The ASU is intended to help stakeholders during the global market-wide reference rate transition period. ASU 2021-01 clarifies that certain optional expedients and exceptions in ASC 848 for contract modifications and hedge accounting apply to derivatives that are affected by the discounting transition. ASU 2021-01 also amends the expedients and exceptions in ASC 848 to capture the incremental consequences of the scope clarification and to tailor the existing guidance to derivative instruments affected by the discounting transition. These ASUs were effective upon issuance and generally can be applied through December 31, 2022. The adoption of these ASUs did not significantly impact our financial statements or disclosures. ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. The guidance issued in this update simplified the accounting for income taxes by eliminating certain exceptions to the guidance in ASC 740 related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition for deferred tax liabilities for outside basis differences. ASU 2019-12 also simplified aspects of the accounting for franchise taxes and enacted changes in tax laws or rates and clarified the accounting for transactions that result in a step-up in the tax basis of goodwill. ASU 2019-12 was effective for the Company on January 1, 2021 and did not have a significant impact on our financial statements. ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40) - Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. This ASU aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by these amendments. This ASU became effective for the Company on January 1, 2020 and did not have a significant impact on its financial statements and disclosures. ASU 2018-13, Fair Value Measurement (Topic 820) - Changes to the Disclosure Requirements for Fair Value Measurement. This ASU modified the disclosure requirements on fair value measurements by requiring that Level 3 fair value disclosures include the range and weighted average of significant unobservable inputs used to develop those fair value measurements. For certain unobservable inputs, an entity may disclose other quantitative information in lieu of the weighted average if the entity determines that other quantitative information would be a more reasonable and rational method to reflect the distribution of unobservable inputs used to develop Level 3 fair value measurements. ASU 2018-13 became effective for the Company on January 1, 2020 and did not have a significant impact on its financial statements and disclosures. ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20), Premium Amortization on Purchased Callable Debt Securities . This ASU requires certain premiums on callable debt securities to be amortized to the earliest call date. The amortization period for callable debt securities purchased at a discount is not impacted. Under current GAAP, premiums on callable debt securities are generally amortized over the contractual life of the security. ASU 2017-08 became effective for the Company on January 1, 2019 and, upon adoption, the Company recognized a cumulative effect adjustment reducing retained earnings by $856, net of the deferred tax impact, but otherwise did not have a significant impact to the Company's consolidated financial statements and disclosures. ASU 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment. This ASU simplified the accounting for goodwill impairment for all entities by requiring impairment charges to be based on the first step in today’s two-step impairment test. Under the guidance, if a reporting unit’s carrying amount exceeds its fair value, an entity will record an impairment charge based on that difference. The impairment charge will be limited to the amount of goodwill allocated to that reporting unit. The standard eliminated the prior requirement to calculate a goodwill impairment charge using Step 2, which required an entity to calculate any impairment charge by comparing the implied fair value of goodwill with its carrying amount. ASU 2017-04 became effective for the Company on January 1, 2020, and did not have a significant impact on its financial statements. ASU 2016-02, Leases (Topic 842)

Statement of Cash Flows

Statement of Cash Flows	12 Months Ended
	Dec. 31, 2021
Supplemental Cash Flow Elements [Abstract]
Statement of Cash Flows	Statement of Cash Flows As allowed by the accounting standards, the Company has chosen to report, on a net basis, its cash receipts and cash payments for time deposits accepted and repayments of those deposits, and loans made to customers and principal collections on those loans. The Company uses the indirect method to present cash flows from operating activities. Other supplemental cash flow information is presented below: Years Ended December 31, 2021 2020 2019 Cash transactions: Interest expense paid $ 65,336 $ 97,246 $ 144,775 Income taxes paid $ 58,083 $ 54,842 $ 40,504 Noncash transactions: Deferred dividend equivalents $ 197 $ — $ — Transfers of loans to other real estate owned $ — $ 5,239 $ 544 Loans to facilitate the sale of other real estate owned $ — $ 2,039 $ 517 Securities purchased, not yet settled $ — $ — $ 9,975 Transfers of loans held for investment to loans held for sale $ — $ — $ 83,526 Right-of-use assets obtained in exchange for lease liabilities $ 5,156 $ 105 $ 35,553 Loans purchased, not yet settled $ 29,332 $ 9,442 $ — Transfer of bank premises to other real estate $ — $ — $ 7,896 Transfer of repurchase agreements to deposits $ — $ — $ 8,475 Supplemental schedule of noncash investing activities from a branch sale during 2019 is as follows: Year ended December 31, 2019 Noncash assets transferred: Loans, including accrued interest $ 796 Premises and equipment 94 Other assets 2 Total assets $ 892 Noncash liabilities transferred: Deposits, including interest $ 27,721 Other liabilities 27 Total liabilities $ 27,748 Cash and cash equivalents transferred in branch sales $ 206 Deposit premium received $ 1,386 Cash paid to buyer, net of deposit premium $ 24,957 Supplemental schedule of noncash investing activities from sale of trust business during 2019 is as follows: Year ended December 31, 2019 Noncash assets transferred: Customer relationship intangible assets, net $ 2,939 Other assets 11 Total assets $ 2,950 Net cash received from sale $ 4,269 Supplemental schedule of noncash investing activities from an acquisition during 2019 is as follows: Year ended December 31, 2019 Noncash assets acquired Certificates of deposit held in other banks $ 262 Securities available for sale 561,052 Restricted stock 27,794 Loans 2,789,868 Premises and equipment 65,786 Other real estate owned 1,829 Goodwill 272,224 Other intangible assets 71,518 Bank owned life insurance 80,837 Other assets 31,987 Total assets acquired $ 3,903,157 Noncash liabilities assumed: Deposits $ 3,108,810 Repurchase agreements 8,475 FHLB advances 142,653 Other borrowings 40,000 Junior subordinated debentures 25,774 Other liabilities 15,477 Total liabilities assumed $ 3,341,189 Cash and cash equivalents acquired from acquisitions $ 39,913 Cash paid to shareholders of acquired banks $ 9 Fair value of common stock issued to shareholders of acquired banks $ 601,872

Securities Available for Sale

Securities Available for Sale	12 Months Ended
	Dec. 31, 2021
Debt Securities, Available-for-sale [Abstract]
Securities Available for Sale	Securities Available for Sale Securities available for sale have been classified in the consolidated balance sheets according to management’s intent. The amortized cost of securities and their approximate fair values at December 31, 2021 and 2020, are as follows: Amortized Cost (1) Gross Gross Fair Securities Available for Sale December 31, 2021 U.S. treasuries $ 174,950 $ 724 $ (678) $ 174,996 Government agency securities 453,402 1,221 (9,948) 444,675 Obligations of state and municipal subdivisions 418,554 15,440 (1,234) 432,760 Corporate bonds 33,994 862 (60) 34,796 Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 917,942 10,757 (10,149) 918,550 Other securities 950 — — 950 $ 1,999,792 $ 29,004 $ (22,069) $ 2,006,727 December 31, 2020 U.S. treasuries $ 43,060 $ 1,648 $ — $ 44,708 Government agency securities 247,764 3,169 (1,916) 249,017 Obligations of state and municipal subdivisions 373,017 20,168 (20) 393,165 Corporate bonds 21,496 608 (2) 22,102 Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 421,916 21,678 (93) 443,501 Other securities 1,200 — — 1,200 $ 1,108,453 $ 47,271 $ (2,031) $ 1,153,693 ____________ (1) Excludes accrued interest receivable of $8,581 and $6,242 at December 31, 2021 and December 31, 2020, respectively, that is recorded in other assets on the accompanying consolidated balance sheets Securities with a carrying amount of approximately $997,416 and $738,519 at December 31, 2021 and 2020, respectively, were pledged primarily to secure deposits. Proceeds from sale of securities available for sale and gross gains and gross losses for the years ended December 31, 2021, 2020 and 2019 were as follows: Years Ended December 31, 2021 2020 2019 Proceeds from sale $ 9,294 $ 13,862 $ 192,417 Gross gains $ 13 $ 385 $ 306 Gross losses $ — $ 3 $ 31 The amortized cost and estimated fair value of securities available for sale at December 31, 2021, by contractual maturity, are shown below. Maturities of mortgage-backed securities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. December 31, 2021 Securities Available for Sale Amortized Cost (1) Fair Due in one year or less $ 31,164 $ 31,526 Due from one year to five years 198,803 202,479 Due from five to ten years 460,251 459,017 Thereafter 391,632 395,155 1,081,850 1,088,177 Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 917,942 918,550 $ 1,999,792 $ 2,006,727 ____________ (1) Excludes accrued interest receivable of $8,581 at December 31, 2021 that is recorded in other assets on the accompanying consolidated balance sheets The number of securities, unrealized losses and fair value, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, as of December 31, 2021 and 2020, are summarized as follows: Less Than 12 Months Greater Than 12 Months Total Description of Securities Number of Securities Estimated Unrealized Number of Securities Estimated Unrealized Estimated Unrealized Securities Available for Sale December 31, 2021 U.S. treasuries 22 $ 144,172 $ (678) — $ — $ — $ 144,172 $ (678) Government agency securities 38 258,334 (4,622) 22 119,963 (5,326) 378,297 (9,948) Obligations of state and municipal subdivisions 14 47,200 (988) 2 3,555 (246) 50,755 (1,234) Corporate bonds 3 13,440 (60) — — — 13,440 (60) Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 115 621,717 (8,471) 11 44,620 (1,678) 666,337 (10,149) 192 $ 1,084,863 $ (14,819) 35 $ 168,138 $ (7,250) $ 1,253,001 $ (22,069) December 31, 2020 Government agency securities 20 112,897 (1,916) — — — 112,897 (1,916) Obligations of state and municipal subdivisions 2 3,786 (20) — — — 3,786 (20) Corporate bonds 1 998 (2) — — — 998 (2) Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 10 41,344 (93) — — — 41,344 (93) 33 $ 159,025 $ (2,031) — $ — $ — $ 159,025 $ (2,031) At December 31, 2021 , management's review of all available for sale securities at an unrealized loss position determined that the losses resulted from factors not related to credit quality. This conclusion is based on management's analysis of the underlying risk characteristics, including credit ratings, and other qualitative factors for each security type in our portfolio. The unrealized losses are generally due to increases in market interest rates. Furthermore, the Company has the intent to hold these securities until maturity or a forecasted recovery, and it is more likely than not that the Company will not have to sell the securities before the recovery of their cost basis. As such, there is no allowance for credit losses on available for sale securities recognized as of December 31, 2021 .

Loans, Net and Allowance for Cr

Loans, Net and Allowance for Credit Losses on Loans	12 Months Ended
	Dec. 31, 2021
Receivables [Abstract]
Loans, Net and Allowance for Loan Losses	Loans, Net and Allowance for Credit Losses on Loans Loans, net at December 31, 2021 and 2020, consisted of the following: December 31, 2021 2020 Commercial $ 1,983,886 $ 2,448,699 Mortgage warehouse purchase loans 788,848 1,453,797 Real estate: Commercial 6,617,455 6,096,676 Commercial construction, land and land development 1,180,181 1,245,801 Residential 1,300,122 1,352,465 Single-family interim construction 380,627 326,575 Agricultural 106,512 85,014 Consumer 81,815 67,068 Total loans (1)(2) 12,439,446 13,076,095 Deferred loan fees, net (1) — (10,037) Allowance for credit losses (148,706) (87,820) Total loans, net (2) $ 12,290,740 $ 12,978,238 ____________ (1) Loan class amounts are shown at amortized cost, net of deferred loan fees of $9,406, in accordance with ASC 326 at December 31, 2021 and shown at recorded investment at December 31, 2020. (2) Excludes accrued interest receivable of $41,051 and $54,328 at December 31, 2021 and December 31, 2020, respectively, that is recorded in other assets on the accompanying consolidated balance sheets. The Company has certain lending policies and procedures in place that are designed to maximize loan income within an acceptable level of risk. Management reviews and approves these policies and procedures on a regular basis. A reporting system supplements the review process by providing management with frequent reports related to loan production, loan quality, concentrations of credit, loan delinquencies and nonperforming and potential problem loans. Commercial loans are underwritten after evaluating and understanding the borrower’s ability to operate profitably and prudently expand its business. The Company’s management examines current and projected cash flows to determine the ability of the borrower to repay their obligations as agreed. Commercial loans are primarily made based on the identified cash flows of the borrower and secondarily on the underlying collateral provided by the borrower. These cash flows, however, may not be as expected and the value of collateral securing the loans may fluctuate. Most commercial loans are secured by the assets being financed or other business assets such as accounts receivable or inventory and may incorporate a personal guarantee; however, some short term loans may be made on an unsecured basis. Our commercial portfolio also includes Shared National Credits (SNC). SNCs are loan participations purchased from upstream financial organizations that are typically larger in size than the Company's originated loan portfolio. In some instances, the Company participates as the lead, originating bank. SNC loans are originated in the normal course of business and are subject to the same underwriting standards as our portfolio loans. SNCs are subject to regular monitoring of performance and credit quality. At December 31, 2021 and 2020, the SNC portfolio totaled $294,351 and $187,589, respectively. Additionally, our commercial loan portfolio includes loans made to customers in the energy industry, which is a complex, technical and cyclical industry. Experienced bankers with specialized energy lending experience originate our energy loans. Companies in this industry produce, extract, develop, exploit and explore for oil and natural gas. Loans are primarily collateralized with proven producing oil and gas reserves based on a technical evaluation of these reserves. At December 31, 2021 and 2020, there were approximately $342,776 and $205,496 of energy-related loans outstanding, respectively. With the passage of the CARES Act Paycheck Protection Program (PPP) in 2020, administered by the Small Business Administration (SBA), the Company participated by originating loans to its customers through the program. PPP loans have terms of two The Company has a mortgage warehouse purchase program providing mortgage inventory financing for residential mortgage loans originated by mortgage banker clients across a broad geographic scale. Proceeds from the sale of mortgages is the primary source of repayment for warehouse inventory financing via approved investor takeout commitments. These loans typically have a very short duration ranging between a few days to 15 days. In some cases, loans to larger mortgage originators may be financed for up to 60 days. Warehouse purchase program loans are collectively evaluated for impairment and are purchased under several contractual requirements, providing safeguards to the Company. To date, the Company has not experienced a loss on these loans and no allowance for credit losses has been allocated to them. Commercial real estate loans are subject to underwriting standards and processes similar to commercial loans. These loans are viewed primarily as cash flow loans and secondarily as loans secured by real estate. Commercial real estate lending typically involves higher loan principal amounts and the repayment of these loans is generally largely dependent on the successful operation of the property or the business conducted on the property securing the loan. Commercial real estate loans may be more adversely affected by conditions in the real estate markets or in the general economy. The properties securing the Company’s commercial real estate portfolio are diverse in terms of type and geographic location. Management monitors the diversification of the portfolio on a quarterly basis by type and geographic location. Management also tracks the level of owner-occupied property versus non owner-occupied property. At December 31, 2021, the portfolio consisted of approximately 26% of owner-occupied property. Land and commercial land development loans are underwritten using feasibility studies, independent appraisal reviews and financial analysis of the developers or property owners. Generally, borrowers must have a proven track record of success. Commercial construction loans are generally based upon estimates of cost and value of the completed project. These estimates may not be accurate. Commercial construction loans often involve the disbursement of substantial funds with the repayment dependent on the success of the ultimate project. Sources of repayment for these loans may be pre-committed permanent financing or sale of the developed property. The loans in this portfolio are geographically diverse and due to the increased risk are monitored closely by management and the board of directors on a quarterly basis. Residential real estate and single-family interim construction loans are underwritten primarily based on borrowers’ credit scores, documented income and minimum collateral values. Relatively small loan amounts are spread across many individual borrowers which minimizes risk in the residential portfolio. In addition, management evaluates trends in past dues and current economic factors on a regular basis. Agricultural loans are collateralized by real estate and/or agricultural-related assets. Agricultural real estate loans are primarily comprised of loans for the purchase of farmland. Loan-to-value ratios on loans secured by farmland generally do not exceed 80% and have amortization periods limited to twenty years. Agricultural non-real estate loans are generally comprised of term loans to fund the purchase of equipment, livestock and seasonal operating lines to grain farmers to plant and harvest corn and soybeans. Specific underwriting standards have been established for agricultural-related loans including the establishment of projections for each operating year based on industry developed estimates of farm input costs and expected commodity yields and prices. Operating lines are typically written for one year and secured by the crop and other farm assets as considered necessary. Agricultural loans carry credit risks as they involve larger balances concentrated with single borrowers or groups of related borrowers. In addition, repayment of such loans depends on the successful operation or management of the farm property securing the loan or for which an operating loan is utilized. Farming operations may be affected by adverse weather conditions such as drought, hail or floods that can severely limit crop yields. Consumer loans represent less than 1% of the outstanding total loan portfolio. Collateral consists primarily of automobiles and other personal assets. Credit score analysis is used to supplement the underwriting process. Most of the Company’s lending activity occurs within the state of Texas, primarily in the north, central and southeast Texas regions and the state of Colorado, specifically along the Front Range area. As of December 31, 2021, loans in the Colorado region represented about 24% of the total portfolio. A large percentage of the Company’s portfolio consists of commercial and residential real estate loans. As of December 31, 2021 and 2020, there were no concentrations of loans related to a single industry in excess of 10% of total loans. As discussed in Note 2. Recent Accounting Standards , on January 1, 2021, the Company adopted ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) (ASC 326). The amount of the allowance represents management's best estimate of current expected credit losses on loans considering available information relevant to assessing collectibility over the loans' contractual terms, adjusted for expected prepayments when appropriate. The contractual term excludes expected extensions, renewals and modifications unless either of the following applies: management has a reasonable expectation that a troubled debt restructuring will be executed with an individual borrower, or the extension or renewal options are included in the borrower contract and are not unconditionally cancellable by the Company. The Company's allowance balance is estimated using relevant available information, from internal and external sources, relating to past events, current conditions and reasonable and supportable forecasts. Historical credit loss experience provides the basis for the estimation of expected credit losses. Adjustments to historical loss information are made for differences in current loan-specific risk characteristics such as differences in underwriting standards, portfolio mix, credit quality, or term as well as for changes in environmental conditions, such as changes in unemployment rates, gross domestic product, property values or other relevant factors. The Company utilizes Moody’s Analytics economic forecast scenarios and assigns probability weighting to those scenarios which best reflect management’s views on the economic forecast. The allowance for credit losses is measured on a collective basis for portfolios of loans when similar risk characteristics exist. Loans that do not share risk characteristics are evaluated for expected credit losses on an individual basis and excluded from the collective evaluation. For determining the appropriate allowance for credit losses on a collective basis, the loan portfolio is segmented into pools based upon similar risk characteristics and a lifetime loss-rate model is utilized. For modeling purposes, loan pools include: commercial and industrial, energy, commercial real estate - construction/land development, commercial real estate - owner occupied, commercial real estate - non-owner occupied, agricultural, residential real estate, HELOCs, single-family interim construction, and consumer. Management periodically reassesses each pool to ensure the loans within the pool continue to share similar characteristics and risk profiles and to determine whether further segmentation is necessary. The measurement of expected credit losses is impacted by loan/borrower attributes and certain macroeconomic variables. Management has determined that they are reasonably able to forecast the macroeconomic variables used in the modeling processes with an acceptable degree of confidence for a total of two years then encompassing a reversion process whereby the forecasted macroeconomic variables are reverted to their historical mean utilizing a rational, systematic basis. Management qualitatively adjusts model results for risk factors that are not considered within the modeling processes but are nonetheless relevant in assessing the expected credit losses within the loan pools. These qualitative factor (Q-Factor) adjustments may increase or decrease management's estimate of expected credit losses by a calculated percentage or amount based upon the estimated level of risk. Loans exhibiting unique risk characteristics and requiring an individual allowance are measured based on 1) the present value of expected future cash flows discounted at the loan's effective interest rate; 2) the loan's observable market price; or 3) the fair value of collateral if the loan is collateral dependent. Substantially all of the Company’s individually evaluated loans are measured at the fair value of the collateral. Management continually evaluates the allowance for credit losses based upon the factors noted above. Should any of the factors considered by management change, the Company’s estimate of credit losses could also change and would affect the level of future provision for credit losses. Portions of the allowance may be allocated for specific credits; however, the entire allowance is available for any credit that, in management’s judgment, should be charged off. While the calculation of the allowance for credit losses utilizes management’s best judgment and all the information available, the adequacy of the allowance for credit losses is dependent on a variety of factors beyond the Company’s control, including, among other things, the performance of the entire loan portfolio, the economy, changes in interest rates and the view of regulatory authorities towards loan classifications. Loans requiring an individual allowance are generally identified at the servicing officer level based on review of weekly past due reports and/or the loan officer’s communication with borrowers. In addition, the status of past due loans are routinely discussed within each lending region as well as credit committee meetings to determine if classification is warranted. The Company’s internal loan review department has implemented an internal risk-based loan review process to identify potential internally classified loans that supplements the independent external loan review. External loan reviews cover a wide range of the loan portfolio, including large lending relationships, specifically targeted loan types, and if applicable recently acquired loan portfolios. As such, the external loan review generally covers loans exceeding $3,000. These reviews include analysis of borrower’s financial condition, payment histories, review of loan documentation and collateral values to determine if a loan should be internally classified. Generally, once classified, an analysis is completed by the credit department to determine the amount of allocated allowance for credit loss required. Expected credit losses for collateral dependent loans, including loans where the borrower is experiencing financial difficulty but foreclosure is not probable, are based on the fair value of the collateral at the reporting date, adjusted for selling costs as appropriate. Following unprecedented declines caused by the pandemic and volatile energy prices, the Texas economy, specifically in the Company’s lending areas of north, central and southeast Texas economy continued robust expansion into the fourth quarter of 2021. The Colorado economy grew at a moderate pace. The stronger sectors of the economy of late include manufacturing, nonfinancial services and residential real estate, while other sectors of the economy where growth slowed were those constrained by supply disruptions and labor shortages. Energy activity and agricultural conditions improved further. Activity in the single-family housing market remained elevated during the reporting period but activity is constrained by labor, lot and material shortages. Overall, the economy is being impacted by persistent labor and supply shortages, and rising costs, which are expected to dampen the recovery. Previous forecasts for a strong return of business travel and events this fall have been adjusted downward by the pandemic resurgence, most recently the Omicron variant. The pandemic continues to have an impact on the economies in the Company's lending areas and the timing and magnitude of recovery cannot be predicted. The risk of loss associated with all segments of the portfolio could increase due to these factors. The economy and other risk factors are minimized by the Company’s underwriting standards which include the following principles: 1) financial strength of the borrower including strong earnings, high net worth, significant liquidity and acceptable debt to worth ratio, 2) managerial business competence, 3) ability to repay, 4) loan to value, 5) projected cash flow and 6) guarantor financial statements as applicable. The following is a summary of the activity in the allowance for credit losses on loans by class for the years ended December 31, 2021, 2020 and 2019: Commercial Commercial Real Estate Commercial Construction, Residential Single-Family Agricultural Consumer Unallocated Total Year ended December 31, 2021 Balance at beginning of year $ 27,311 $ 36,698 $ 13,425 $ 6,786 $ 2,156 $ 337 $ 684 $ 423 $ 87,820 Impact of adopting ASC 326 12,775 29,108 22,008 (2,255) 7,179 (178) (334) (423) 67,880 Initial allowance on loans purchased with credit deterioration 4,328 7,640 927 140 — — — — 13,035 Provision for credit losses 12,130 (7,961) (12,373) (2,486) (2,113) (53) 247 — (12,609) Charge-offs (6,856) (375) (126) — — — (174) — (7,531) Recoveries 59 — — 7 — — 45 — 111 Balance at end of year $ 49,747 $ 65,110 $ 23,861 $ 2,192 $ 7,222 $ 106 $ 468 $ — $ 148,706 Year ended December 31, 2020 Balance at beginning of year $ 12,844 $ 24,371 $ 8,714 $ 3,678 $ 1,606 $ 332 $ 231 $ (315) $ 51,461 Provision for credit losses 20,025 13,058 4,711 3,108 632 5 716 738 42,993 Charge-offs (5,670) (735) — — (82) — (386) — (6,873) Recoveries 112 4 — — — — 123 — 239 Balance at end of year $ 27,311 $ 36,698 $ 13,425 $ 6,786 $ 2,156 $ 337 $ 684 $ 423 $ 87,820 Year ended December 31, 2019 Balance at beginning of year $ 11,793 $ 21,343 $ 6,452 $ 3,320 $ 1,402 $ 241 $ 189 $ 62 $ 44,802 Provision for credit losses 8,670 3,027 2,262 498 207 91 427 (377) 14,805 Charge-offs (7,709) (3) — (140) (3) — (509) — (8,364) Recoveries 90 4 — — — — 124 — 218 Balance at end of year $ 12,844 $ 24,371 $ 8,714 $ 3,678 $ 1,606 $ 332 $ 231 $ (315) $ 51,461 The Company will charge-off that portion of any loan which management considers a loss. Commercial and real estate loans are generally considered for charge-off when exposure beyond collateral coverage is apparent and when no further collection of the loss portion is anticipated based on the borrower’s financial condition. The following table presents loans that were evaluated for expected credit losses on an individual basis and the related specific credit loss allocations, by loan class as of December 31, 2021 and December 31, 2020: December 31, 2021 December 31, 2020 Loan Balance - Specific Allocations Loan Balance - Specific Allocations Commercial $ 38,911 $ 15,958 $ 39,298 $ 8,281 Commercial real estate 24,683 1,553 21,848 243 Commercial construction, land and land development 1,350 562 32 — Residential real estate — — 2,550 — Single-family Interim construction — — — — Agricultural — — 613 — Consumer — — 42 — $ 64,944 $ 18,073 $ 64,383 $ 8,524 Nonperforming loans by loan class at December 31, 2021 (at amortized cost) and December 31, 2020 (at recorded investment), are summarized as follows: Commercial Commercial Construction, Residential Real Estate Single-Family Agricultural Consumer Total December 31, 2021 Nonaccrual loans (1) $ 36,802 $ 15,218 $ 23 $ 1,592 $ — $ — $ 38 $ 53,673 Loans past due 90 days and still accruing 187 — — 1,603 — — — 1,790 Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing) — 1,714 — 161 — — — 1,875 $ 36,989 $ 16,932 $ 23 $ 3,356 $ — $ — $ 38 $ 57,338 December 31, 2020 (2) Nonaccrual loans $ 25,898 $ 20,040 $ 32 $ 2,372 $ — $ 613 $ 42 $ 48,997 Loans past due 90 days and still accruing 433 — — — — — — 433 Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing) — 1,808 — 178 — — — 1,986 $ 26,331 $ 21,848 $ 32 $ 2,550 $ — $ 613 $ 42 $ 51,416 ____________ (1) There is one nonaccrual loan totaling $18 without an allowance for credit loss as of December 31, 2021. Additionally, no interest income was recognized on nonaccrual loans. No significant amounts of accrued interest was reversed during the year ended December 31, 2021. (2) Excluded loans acquired with deteriorated credit quality under prior GAAP The accrual of interest is discontinued on a loan when management believes that, after considering collection efforts and other factors, the borrower's financial condition is such that collection of interest is doubtful, as well as when required by regulatory provisions. Regulatory provisions would typically require the placement of a loan on non-accrual status if 1) principal or interest has been in default for a period of 90 days or more unless the loan is both well secured and in the process of collection or 2) full payment of principal and interest is not expected. All interest accrued but not collected for loans that are placed on nonaccrual status or charged-off is reversed against interest income. Cash collections on nonaccrual loans are generally credited to the loan receivable balance, and no interest income is recognized on those loans until the principal balance has been collected. Loans are generally returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured. The restructuring of a loan is considered a “troubled debt restructuring” (TDR) if both 1) the borrower is experiencing financial difficulties and 2) the creditor has granted a concession. Concessions may include interest rate reductions or below market interest rates, principal forgiveness, extending amortization and other actions intended to minimize potential losses. Modifications primarily relate to extending the amortization periods of the loans and interest rate concessions. The modifications during the reported periods did not materially impact the Company’s determination of the allowance for credit losses. The amortized cost basis and recorded investment in troubled debt restructurings, including those on nonaccrual, was $2,918 and $2,564 as of December 31, 2021 and 2020, respectively. Following is a summary of loans modified under troubled debt restructurings during the years ended December 31, 2021 and 2020: Commercial Commercial Commercial Construction, Residential Single-Family Agricultural Consumer Total Troubled debt restructurings during the year ended December 31, 2021 Number of contracts 2 — — — — — 1 3 Pre-restructuring outstanding recorded investment $ 1,789 $ — $ — $ — $ — $ — $ 6 $ 1,795 Post-restructuring outstanding recorded investment $ 570 $ — $ — $ — $ — $ — $ 6 $ 576 Troubled debt restructurings during the year ended December 31, 2020 Number of contracts — 1 — — — — — 1 Pre-restructuring outstanding recorded investment $ — $ 1,517 $ — $ — $ — $ — $ — $ 1,517 Post-restructuring outstanding recorded investment $ — $ 1,517 $ — $ — $ — $ — $ — $ 1,517 At December 31, 2021 and 2020, there were no loans modified under troubled debt restructurings during the previous twelve month period that subsequently defaulted during the years ended December 31, 2021 and 2020. At December 31, 2021 and 2020, the Company had no commitments to lend additional funds to any borrowers with loans whose terms have been modified under troubled debt restructurings. Under ASC Subtopic 310-40 and federal banking agencies interagency guidance, certain short-term loan modifications made on a good faith basis in response to COVID-19 (as defined by the guidance) are not considered TDRs. Additionally, under section 4013 of the CARES Act, and as amended, banks may elect to suspend the requirement for certain loan modifications to be categorized as a TDR. In response to the COVID-19 pandemic, the Company has implemented prudent modifications allowing for primarily short-term payment deferrals or other payment relief to borrowers with pandemic-related economic hardships, where appropriate, that complies with the above guidance. As such, the Company's TDR loans noted above do not include loans that are modifications to borrowers impacted by COVID-19. As of December 31, 2021, the amount of loans remaining in COVID-19 related deferment was not significant. Loans are considered past due if the required principal and interest payments have not been received as of the date such payments were due. The following table presents information regarding the aging of past due loans by loan class as of December 31, 2021 (at amortized cost) and as of December 31, 2020 (at recorded investment): Loans Loans Total Past Current Total December 31, 2021 Commercial $ 1,041 $ 11,056 $ 12,097 $ 1,971,789 $ 1,983,886 Mortgage warehouse — — — 788,848 788,848 Commercial real estate 2,861 11,784 14,645 6,602,810 6,617,455 Commercial construction, land and land development — — — 1,180,181 1,180,181 Residential real estate 3,838 1,913 5,751 1,294,371 1,300,122 Single-family interim construction 1,290 — 1,290 379,337 380,627 Agricultural 16 — 16 106,496 106,512 Consumer 216 9 225 81,590 81,815 $ 9,262 $ 24,762 $ 34,024 $ 12,405,422 $ 12,439,446 December 31, 2020 (1) Commercial $ 3,243 $ 13,227 $ 16,470 $ 2,393,013 $ 2,409,483 Mortgage warehouse — — — 1,453,797 1,453,797 Commercial real estate 2,434 16,790 19,224 5,921,723 5,940,947 Commercial construction, land and land development 19 — 19 1,230,524 1,230,543 Residential real estate 5,169 1,028 6,197 1,341,587 1,347,784 Single-family interim construction — — — 326,575 326,575 Agricultural — 1 1 84,896 84,897 Consumer 86 41 127 67,156 67,283 10,951 31,087 42,038 12,819,271 12,861,309 Acquired with deteriorated credit quality 624 3,219 3,843 210,943 214,786 $ 11,575 $ 34,306 $ 45,881 $ 13,030,214 $ 13,076,095 ____________ (1) Presented under prior GAAP The Company’s internal classified report is segregated into the following categories: 1) Pass/Watch, 2) Special Mention, 3) Substandard and 4) Doubtful. The loans placed in the Pass/Watch category reflect the Company’s opinion that the loans reflect potential weakness that requires monitoring on a more frequent basis. The loans in the Special Mention category reflect the Company’s opinion that the credit contains weaknesses which represent a greater degree of risk and warrant extra attention. These loans are reviewed monthly by officers and senior management to determine if a change in category is warranted. The loans placed in the Substandard category are considered to be potentially inadequately protected by the current debt service capacity of the borrower and/or the pledged collateral. These credits, even if apparently protected by collateral value, have shown weakness related to adverse financial, managerial, economic, market or political conditions, which may jeopardize repayment of principal and interest and may be considered impaired. There is a possibility that some future loss could be sustained by the Company if such weakness is not corrected. The Doubtful category includes loans that are in default or principal exposure is probable and the possibility of loss is extremely high. Management considers the guidance in ASC 310-20 when determining whether a modification, extension or renewal of a loan constitutes a current period origination. Generally, current period renewals of credit are re-underwritten at the point of renewal and considered current period originations for purposes of the table below. The following summarizes the amortized cost basis of loans by year of origination/renewal and credit quality indicator by class of loan as of December 31, 2021: Revolving Loans Converted to Term Loans Term Loans by Year of Origination or Renewal Revolving Loans December 31, 2021 2021 2020 2019 2018 2017 Prior Total Commercial Pass $ 422,810 $ 183,433 $ 98,059 $ 78,357 $ 81,620 $ 255,213 $ 690,242 $ 5,231 $ 1,814,965 Pass/Watch 260 3,010 1,019 3,135 11,688 65 18,768 3,319 41,264 Special Mention 1,411 117 8,517 7,244 195 4,571 12,885 — 34,940 Substandard 30,277 605 16,041 94 2,478 18,331 13,006 1,988 82,820 Doubtful — — — — — — 9,897 — 9,897 Total commercial $ 454,758 $ 187,165 $ 123,636 $ 88,830 $ 95,981 $ 278,180 $ 744,798 $ 10,538 $ 1,983,886 Mortgage warehouse Pass $ 788,848 $ — $ — $ — $ — $ — $ — $ — $ 788,848 Pass/Watch — — — — — — — — — Special Mention — — — — — — — — — Substandard — — — — — — — — — Doubtful — — — — — — — — — Total mortgage warehouse $ 788,848 $ — $ — $ — $ — $ — $ — $ — $ 788,848 Commercial real estate Pass $ 2,181,292 $ 1,198,508 $ 830,902 $ 645,470 $ 504,126 $ 626,292 $ 71,850 $ 4,320 $ 6,062,760 Pass/Watch 54,671 18,591 39,045 60,955 30,196 74,762 752 1,319 280,291 Special Mention 56,142 16,770 37,331 29,962 17,649 20,100 — — 177,954 Substandard 36,263 16,118 1,136 11,901 281 29,686 1,065 — 96,450 Doubtful — — — — — — — — — Total commercial real estate $ 2,328,368 $ 1,249,987 $ 908,414 $ 748,288 $ 552,252 $ 750,840 $ 73,667 $ 5,639 $ 6,617,455 Revolving Loans Converted to Term Loans Term Loans by Year of Origination or Renewal Revolving Loans December 31, 2021 2021 2020 2019 2018 2017 Prior Total Commercial construction, land and land development Pass $ 618,288 $ 262,136 $ 98,007 $ 85,596 $ 13,751 $ 14,939 $ 18,586 $ — $ 1,111,303 Pass/Watch 17,899 10,459 6,869 — — 84 — — 35,311 Special Mention 3,780 — — — 1,909 — — — 5,689 Substandard 11,601 — 387 14,489 28 1,373 — — 27,878 Doubtful — — — — — — — — — Total commercial construction, land and land development $ 651,568 $ 272,595 $ 105,263 $ 100,085 $ 15,688 $ 16,396 $ 18,586 $ — $ 1,180,181 Residential real estate Pass $ 408,402 $ 267,147 $ 190,890 $ 114,616 $ 88,295 $ 149,871 $ 60,212 $ 2,344 $ 1,281,777 Pass/Watch 1,019 487 1,270 405 2,331 4,179 169 — 9,860 Special Mention 657 — 568 129 250 1,043 126 — 2,773 Substandard 640 369 384 519 774 2,974 52 — 5,712 Doubtful — — — — — — — — — Total residential real estate $ 410,718 $ 268,003 $ 193,112 $ 115,669 $ 91,650 $ 158,067 $ 60,559 $ 2,344 $ 1,300,122 Single-family interim construction Pass $ 305,267 $ 59,584 $ 2,801 $ 312 $ — $ — $ 12,663 $ — $ 380,627 Pass/Watch — — — — — — — — — Special Mention — — — — — — — — — Substandard — — — — — — — — — Doubtful — — — — — — — — — Total single-family interim construction $ 305,267 $ 59,584 $ 2,801 $ 312 $ — $ — $ 12,663 $ — $ 380,627 Agricultural Pass $ 36,442 $ 15,005 $ 4,454 $ 8,033 $ 12,229 $ 4,773 $ 18,993 $ — $ 99,929 Pass/Watch — 526 1,462 52 1,035 — 3,502 — 6,577 Special Mention — — — — — — — — — Substandard — — — — — 6 — — 6 Doubtful — — — — — — — — — Total agricultural $ 36,442 $ 15,531 $ 5,916 $ 8,085 $ 13,264 $ 4,779 $ 22,495 $ — $ 106,512 Consumer Pass $ 10,568 $ 9,496 $ 2,706 $ 710 $ 308 $ 181 $ 57,744 $ 43 $ 81,756 Pass/Watch — — — — 1 — — — 1 Special Mention — — — — — — — — — Substandard 30 2 — — 9 17 — — 58 Doubtful — — — — — — — — — Total consumer $ 10,598 $ 9,498 $ 2,706 $ 710 $ 318 $ 198 $ 57,744 $ 43 $ 81,815 Revolving Loans Converted to Term Loans Term Loans by Year of Origination or Renewal Revolving Loans December 31, 2021 2021 2020 2019 2018 2017 Prior Total Total loans Pass $ 4,771,917 $ 1,995,309 $ 1,227,819 $ 933,094 $ 700,329 $ 1,051,269 $ 930,290 $ 11,938 $ 11,621,965 Pass/Watch 73,849 33,073 49,665 64,547 45,251 79,090 23,191 4,638 373,304 Special Mention 61,990 16,887 46,416 37,335 20,003 25,714 13,011 — 221,356 Substandard 78,811 17,094 17,948 27,003 3,570 52,387 14,123 1,988 212,924 Doubtful — — — — — — 9,897 — 9,897 Total loans $ 4,986,567 $ 2,062,363 $ 1,341,848 $ 1,061,979 $ 769,153 $ 1,208,460 $ 990,512 $ 18,564 $ 12,439,446 A summary of loans at recorded investment by credit quality indicator by class presented under prior GAAP as of December 31, 2020, is as follows: Pass Pass/ Special Mention Substandard Doubtful Total December 31, 2020 Commercial $ 2,247,059 $ 55,960 $ 38,186 $ 97,403 $ 10,091 $ 2,448,699 Mortgage warehouse 1,453,797 — — — — 1,453,797 Commercial real estate 5,379,801 306,884 317,580 92,411 — 6,096,676 Construction, land and land development 1,125,132 46,026 43,383 31,260 — 1,245,801 Residential real estate 1,332,757 6,296 5,726 7,686 — 1,352,465 Single-family interim construction 323,800 2,775 — — — 326,575 Agricultural 76,951 6,194 1,205 664 —

Premises and Equipment, Net

Premises and Equipment, Net	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Premises and Equipment, Net	Premises and Equipment, Net Premises and equipment, net at December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Land $ 78,900 $ 65,103 Building 193,475 191,940 Furniture, fixtures and equipment 47,576 39,282 Aircraft 8,947 8,947 Leasehold and tenant improvements 5,834 5,798 Construction in progress 45,263 915 379,995 311,985 Less accumulated depreciation (71,972) (62,518) $ 308,023 $ 249,467 Depreciation expense amounted to $12,385, $12,728 and $11,783 for the years ended December 31, 2021, 2020 and 2019, respectively.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets, Net	12 Months Ended
	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets, Net	Goodwill and Other Intangible Assets, Net At December 31, 2021 and 2020, goodwill totaled $994,021. The following is a summary of other intangible assets activity: December 31, 2021 2020 Core deposit intangible: Balance at end of the year $ 125,884 $ 125,884 Less accumulated amortization (55,323) (43,235) Total core deposit intangible, net $ 70,561 $ 82,649 Customer relationship intangible: Balance at end of the year $ 6,407 $ 6,407 Less accumulated amortization (1,478) (986) Total customer relationship intangible, net $ 4,929 $ 5,421 Total other intangible assets, net $ 75,490 $ 88,070 Amortization expense related to intangible assets amounted to $12,580, $12,671 and $12,880 for the years ended December 31, 2021, 2020 and 2019, respectively. The remaining weighted average amortization period for intangible assets is 6.5 years as of December 31, 2021. The future amortization expense related to other intangible assets remaining at December 31, 2021 is as follows: First year $ 12,491 Second year 12,439 Third year 11,752 Fourth year 11,238 Fifth year 10,801 Thereafter 16,769 $ 75,490

Deposits

Deposits	12 Months Ended
	Dec. 31, 2021
Deposits [Abstract]
Deposits	Deposits Deposits at December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Amount Percent Amount Percent Noninterest-bearing demand accounts $ 5,066,588 32.6 % $ 4,164,800 28.9 % Interest-bearing checking accounts 6,234,344 40.1 5,420,548 37.6 Savings accounts 758,727 4.9 654,733 4.6 Money market accounts 2,431,965 15.6 2,743,208 19.1 Certificates of deposit and individual retirement accounts (IRA), less than $250,000 540,011 3.5 675,329 4.7 Certificates of deposit and individual retirement accounts (IRA), $250,000 and greater 522,273 3.3 740,309 5.1 $ 15,553,908 100.0 % $ 14,398,927 100.0 % At December 31, 2021, the scheduled maturities of certificates of deposit, including IRAs, were as follows: First year $ 928,258 Second year 101,081 Third year 12,432 Fourth year 10,709 Fifth year 9,804 $ 1,062,284

Federal Home Loan Bank Advances

Federal Home Loan Bank Advances	12 Months Ended
	Dec. 31, 2021
Advances from Federal Home Loan Banks [Abstract]
Federal Home Loan Bank Advances	Federal Home Loan Bank Advances At December 31, 2021, the Company has advances from the FHLB of Dallas under note payable arrangements that mature in 2035. Interest payments on these notes are made monthly. The weighted average interest rate of all notes was 0.48% and 0.57% at December 31, 2021 and 2020, respectively. The balances outstanding on these advances were $150,000 and $375,000 at December 31, 2021 and 2020, respectively. The advances are secured by $18,546 of FHLB stock owned by the Company and a blanket lien on certain loans along with specific listed loans for an aggregate available carrying value of $5,581,162 at December 31, 2021. The Company had remaining credit available under the FHLB advance program of $3,952,344 at December 31, 2021. At December 31, 2021, the Company had $1,473,105 in undisbursed advance commitments (letters of credit) with the FHLB. As of December 31, 2021, these commitments mature on various dates from January 2022 through January 2023. The FHLB letters of credit were obtained in lieu of pledging securities to secure public fund deposits that are over the FDIC insurance limit. At December 31, 2021, there were no disbursements against the advance commitments.

Other Borrowings

Other Borrowings	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Other Borrowings	Other Borrowings Other borrowings at December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Unsecured fixed rate subordinated debentures in the amount of $110,000. The balance of borrowings at December 31, 2021 and 2020 is net of discount and origination costs of $913 and $1,271, respectively. Interest payments of 5.875% are made semiannually on February 1 and August 1. The maturity date is August 1, 2024. The notes may not be redeemed prior to maturity and meet the criteria to be recognized as Tier 2 capital for regulatory purposes. (1)(2) $ 109,087 $ 108,729 Unsecured fixed-to-floating subordinated debentures in the original amount of $40,000. Interest payments initially of 5.75% are made semiannually on January 20 and July 20 through July 20, 2021. Thereafter, floating rate payments of 3 month LIBOR plus 4.73% are made quarterly in arrears beginning on October 20, 2021. The maturity date is July 20, 2026 with an optional redemption at July 20, 2021. (3) — 40,000 Unsecured fixed-to-floating subordinated debentures in the amount of $30,000. The balance of borrowings at December 31, 2021 and 2020 is net of origination costs of $465 and $543, respectively. Interest payments initially of 5.00% fixed rate are made semiannually on June 30 and December 31 through December 31, 2022. Thereafter, floating rate payments of 3 month LIBOR plus 2.83% are made quarterly in arrears beginning on March 31, 2023. The maturity date is December 31, 2027 with an optional redemption at December 31, 2022. The notes meet the criteria to be recognized as Tier 2 capital for regulatory purposes. (2) 29,535 29,457 Unsecured fixed-to-floating subordinated debentures in the amount of $130,000. The balance of borrowings at December 31, 2021 and 2020 is net of origination costs of $2,251 and $2,511, respectively. Interest payments initially of 4.00% fixed rate are made semiannually on March 15 and September 15 through September 15, 2025. Thereafter, floating rate payments equal to a benchmark rate (which is expected to be 3 month Secured Overnight Financing Rate (SOFR)) plus 3.885% payable quarterly in arrears beginning on December 15, 2025. The maturity date is September 15, 2030 with an optional redemption at September 15, 2025. The notes meet the criteria to be recognized as Tier 2 capital for regulatory purposes. (2) 127,749 127,489 Unsecured revolving line of credit with an unrelated commercial bank in the amount of $100,000. The line bears interest at LIBOR plus 1.75% and matured January 17, 2022. The Company is required to meet certain financial covenants on a quarterly basis, which includes certain restrictions on cash at IBG and meeting minimum capital ratios. (4) 17,000 6,500 $ 283,371 $ 312,175 ____________ (1) At December 31, 2021 and 2020, other borrowings included amounts owed to related parties of $50. (2) The permissible portion of qualified subordinated notes decreases 20% per year during the final five years of the term of the notes. (3) On July 20, 2021, the Company redeemed $40,000 of its outstanding 5.75% fixed-to-floating rate subordinated debentures. (4) Subsequent to December 31, 2021, the Company renewed the line (see Note 22. Subsequent Events ). The Company has established federal funds lines of credit notes with eleven unaffiliated banks totaling $400,000 of borrowing capacity at December 31, 2021 and nine unaffiliated banks totaling $365,000 of borrowing capacity at December 31, 2020. At December 31, 2021, two of the lines totaling $30,000 have stated maturity dates in May and September 2022. The remaining lines have no stated maturity dates and the lenders may terminate the lines at any time without notice. The lines are provided on an unsecured basis and must be repaid the following business day from when the funds are borrowed. There were no borrowings against the lines at December 31, 2021 and 2020. In addition, the Company maintains a secured line of credit with the Federal Reserve Bank with an availability to borrow approximately $851,051 and $716,700 at December 31, 2021 and 2020, respectively. Approximately $1,195,362 and $1,034,467 of certain loans and securities were pledged as collateral at December 31, 2021 and 2020, respectively. There were no borrowings against this line as of December 31, 2021 and 2020.

Junior Subordinated Debentures

Junior Subordinated Debentures	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Junior Subordinated Debentures	Junior Subordinated Debentures The Company has formed or acquired nine statutory business trusts (the Trusts) for the purpose of issuing trust preferred securities. Each of the Trusts have issued capital and common securities and invested the proceeds thereof in an equivalent amount of junior subordinated debentures (the Debentures) issued by the Company. The interest rate payable on, and the payment terms of the Debentures are the same as the distribution rate and payment terms of the respective issues of capital and common securities issued by the Trusts. The Debentures are subordinated and junior in right of payment to all present and future senior indebtedness. The Company has fully and unconditionally guaranteed the obligations of each of the Trusts with respect to the capital and common securities. Except under certain circumstances, the common securities issued to the Company by the trusts possess sole voting rights with respect to matters involving those entities. Under certain circumstances, the Company may, from time to time, defer the debentures' interest payments, which would result in a deferral of distribution payments on the related trust preferred securities and, with certain exceptions, prevent the Company from declaring or paying cash distributions on the Company's common stock and any other future debt ranking equally with or junior to the debentures. The Company may redeem the debentures, which are intended to qualify as Tier 1 capital, at the Company’s option, subject to approval of the Federal Reserve. As of December 31, 2021 and 2020, the carrying amount of debentures outstanding totaled $54,221 and $54,023, respectively. Information regarding the Debentures as of December 31, 2021 are summarized in the table below: Trust Preferred Securities Issued Debentures Carrying Value Repricing Frequency Interest Rate Interest Rate Index Maturity Date IB Trust I $ 5,155 $ 5,155 Quarterly 3.38% LIBOR + 3.25% March 2033 Guaranty Trust III 10,310 10,310 Quarterly 3.22 LIBOR + 3.10 July 2033 IB Trust II 3,093 3,093 Quarterly 2.97 LIBOR + 2.85 March 2034 Cenbank Trust III 15,464 15,464 Quarterly 2.77 LIBOR + 2.65 April 2034 IB Trust III 3,712 3,712 Quarterly 2.56 LIBOR +2.40 December 2035 IB Centex Trust I 2,578 2,578 Quarterly 3.41 LIBOR + 3.25 February 2035 Community Group Statutory Trust I 3,609 3,609 Quarterly 1.80 LIBOR + 1.60 June 2037 Northstar Trust II (1) 5,155 3,969 Quarterly 1.87 LIBOR + 1.67 June 2037 Northstar Trust III (1) 8,248 6,331 Quarterly 1.87 LIBOR + 1.67 September 2037 $ 57,324 $ 54,221 ____________

Leases

Leases	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Leases	Leases The Company’s primary leasing activities relate to certain real estate operating leases entered into in support of the Company’s branch operations and back office operations. The Company leases 21 of its 93 branches. The Company’s branch locations operated under lease agreements have all been designated as operating leases. In addition, the Company leases certain equipment under operating leases. The Company does not have leases designated as finance leases. As of December 31, 2021 and 2020 the Company’s lease ROU assets were $24,126 and $24,841, respectively, and related lease liabilities were $23,573 and $23,413, respectively. Leases have remaining terms ranging from 1 to 29 years, including extension options that the Company is reasonably certain will be exercised. The table below summarizes net lease cost: Years Ended December 31, 2021 2020 2019 Operating lease cost $ 6,567 $ 6,937 $ 7,025 Short term lease cost 64 124 103 Variable lease cost 1,645 1,631 1,829 Sublease income (282) (221) (228) Net lease cost $ 7,994 $ 8,471 $ 8,729 The table below summarizes other information related to operating leases: Years Ended December 31, 2021 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 5,740 $ 6,091 Weighted average remaining lease term - operating leases, in years 7.41 7.23 Weighted average discount rate - operating leases 3.01 % 3.47 % The following table outlines lease payment obligations as outlined in the Company’s lease agreements for each of the next five years and thereafter in addition to a reconcilement to the Company’s current lease liability as of December 31, 2021. 2022 $ 5,308 2023 4,704 2024 4,109 2025 3,328 2026 1,882 Thereafter 6,921 Total lease payments 26,252 Less imputed interest (2,679) $ 23,573 As of December 31, 2021, the Company had not entered into any material leases that have not yet commenced.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense for the years ended December 31, 2021, 2020 and 2019 was as follows: Years Ended December 31, 2021 2020 2019 Current income tax expense $ 52,130 $ 52,806 $ 39,426 Deferred income tax expense (benefit) 5,353 (1,633) 14,102 Income tax expense, as reported $ 57,483 $ 51,173 $ 53,528 A reconciliation between reported income tax expense and the amounts computed by applying the U.S. federal statutory income tax rate of 21% for the years ended December 31, 2021, 2020 and 2019 to income before income taxes is presented below: Years Ended December 31, 2021 2020 2019 Income tax expense computed at the statutory rate $ 59,269 $ 53,000 $ 51,715 Tax-exempt interest income from municipal securities (1,752) (1,779) (1,781) Tax-exempt loan income (1,359) (1,245) (1,174) Bank owned life insurance income (1,094) (1,123) (1,288) Non-deductible acquisition expenses — — 281 State taxes, net of federal benefit 2,516 2,660 3,455 Non-deductible compensation 473 — 2,017 Net tax expense (benefit) from stock based compensation (691) 243 21 Other 121 (583) 282 $ 57,483 $ 51,173 $ 53,528 Components of deferred tax assets and liabilities are presented in the table below. Deferred taxes as of December 31, 2021 and 2020 are based on the U.S. statutory federal income tax rate of 21%. December 31, 2021 2020 Deferred tax assets: Allowance for loan losses $ 33,463 $ 19,238 Lease liabilities under operating leases 5,141 5,129 NOL and tax credit carryforwards from acquisitions 3,354 3,718 Net unrealized loss on cash flow hedge 221 — Acquired loan fair market value adjustments 5,750 12,986 Stock-based compensation 1,822 1,567 Reserve for bonuses and other accrued expenses 3,775 3,409 Deferred loan fees and costs, net 2,800 — Acquired securities 1,611 2,095 Acquired intangibles 1,213 1,369 Start up costs 117 171 Unearned income 503 715 Deferred compensation 628 857 Noncompete agreements 540 597 Nonaccrual loans 463 550 Other 546 727 61,947 53,128 Deferred tax liabilities: Premises and equipment (10,376) (12,392) Right-of-use assets under operating leases (4,934) (4,911) Net unrealized gain on available for sale securities (1,457) (9,501) Intangible assets (16,464) (19,293) Acquired junior subordinated debentures fair value adjustment (677) (723) PPP deferred loan costs (192) (952) FHLB and other restricted stocks (335) (308) Acquired tax goodwill (735) (572) Other (599) (543) (35,769) (49,195) Net deferred tax asset $ 26,178 $ 3,933 At December 31, 2021, the Company had federal net operating loss carryforwards of approximately $14,237 which expire in various years from 2024 to 2032 and state net operating loss carryforwards of approximately $10,146 which expire in various years from 2025 to 2027. Deferred tax assets are recognized for net operating losses because the benefit is more likely than not to be realized. No valuation allowance for deferred tax assets was recorded at December 31, 2021 or 2020 as management believes it is more likely than not that all of the deferred tax assets will be realized.

Off-Balance Sheet Arrangements,

Off-Balance Sheet Arrangements, Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Off-Balance Sheet Arrangements, Commitments and Contingencies	Off-Balance Sheet Arrangements, Commitments and Contingencies Financial Instruments with Off-Balance Sheet Risk The Company is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. The commitments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the balance sheet. The Company’s exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit is represented by the contractual amount of this instrument. The Company uses the same credit policies in making commitments and conditional obligations as it does for on-balance sheet instruments. At December 31, 2021 and 2020, the approximate amounts of these financial instruments were as follows: December 31, 2021 2020 Commitments to extend credit $ 2,770,036 $ 2,268,216 Standby letters of credit 30,007 25,917 $ 2,800,043 $ 2,294,133 Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Company evaluates each customer’s credit worthiness on a case-by-case basis. The amount of collateral obtained if deemed necessary by the Company upon extension of credit is based on management’s credit evaluation of the counterparty. Collateral held varies but may include accounts receivable, inventory, farm crops, property, plant and equipment and income-producing commercial properties. Letters of credit are written conditional commitments used by the Company to guarantee the performance of a customer to a third party. The Company’s policies generally require that letter of credit arrangements contain security and debt covenants similar to those contained in loan arrangements. In the event the customer does not perform in accordance with the terms of the agreement with the third party, the Company would be required to fund the commitment. The maximum potential amount of future payments the Company could be required to make is represented by the contractual amount shown in the table above. If the commitment is funded, the Company would be entitled to seek recovery from the customer. Allowance For Credit Losses on Off-Balance Sheet Credit Exposures The allowance for credit losses on off-balance sheet credit exposures is calculated under ASC 326, representing expected credit losses over the contractual period for which the Company is exposed to credit risk resulting from a contractual obligation to extend credit. Off-balance sheet credit exposures primarily consist of amounts available under outstanding lines of credit and letters of credit detailed in the table above. The allowance for credit losses on off-balance sheet credit exposures is estimated by loan segment at each balance sheet date using the same methodologies as portfolio loans, taking into consideration the likelihood that funding will occur based on historical utilization rates. The allowance is included in other liabilities on the Company’s consolidated balance sheets. The allowance for credit losses on off-balance sheet commitments was as follows: December 31, 2021 2020 2019 Balance at beginning of period $ — $ — $ — Impact of CECL adoption 1,113 — — Provision for off-balance sheet credit exposure 3,609 — — Balance at end of period $ 4,722 $ — $ — Litigation The Company is involved in certain legal actions arising from normal business activities. Management believes that the outcome of such proceedings will not materially affect the financial position, results of operations or cash flows of the Company. A legal proceeding that the Company believes could become material is described below. The Bank is a party to a legal proceeding inherited in connection with its acquisition of BOH Holdings, Inc. and its subsidiary, Bank of Houston (BOH). The plaintiffs in the case are alleging that the Bank aided and abetted or participated in a fraudulent scheme. The Bank is pursuing insurance coverage for these claims, including reimbursement for defense costs. The Company believes the claims made in this lawsuit are without merit and is vigorously defending the lawsuit. The Company is unable to predict when the matter will be resolved, the ultimate outcome or potential costs or damages to be incurred.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions In the ordinary course of business, the Company has and expects to continue to have transactions, including loans to its officers, directors and their affiliates. In the opinion of management, such transactions are on the same terms as those prevailing at the time for comparable transactions with unaffiliated persons. Loan activity for officers, directors and their affiliates for the year ended December 31, 2021 is as follows: Balance at beginning of year $ 32,471 New loan originations 30,977 Repayments (21,596) Changes in affiliated persons (7,225) Balance at end of year $ 34,627 See Note 10, Other Borrowings , for related party borrowings.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
	Dec. 31, 2021
Retirement Benefits [Abstract]
Employee Benefit Plans	Employee Benefit PlansThe Company has a 401(k) profit sharing plan (Plan) which covers employees over the age of eighteen

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The fair value of an asset or liability is the price that would be received to sell that asset or paid to transfer that liability in an orderly transaction occurring in the principal market (or most advantageous market in the absence of a principal market) for such asset or liability. In estimating fair value, the Company utilizes valuation techniques that are consistent with the market approach, the income approach and/or the cost approach. Such valuation techniques are consistently applied. Inputs to valuation techniques include the assumptions that market participants would use in pricing an asset or liability. ASC Topic 820, Fair Value Measurements and Disclosures , establishes a fair value hierarchy for valuation inputs that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The fair value hierarchy is as follows: Level 1 Inputs – Unadjusted quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. Level 2 Inputs – Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. These might include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (such as interest rates, volatilities, prepayment speeds, credit risks, etc.) or inputs that are derived principally from or corroborated by market data by correlation or other means. Level 3 Inputs – Unobservable inputs for determining the fair values of assets or liabilities that reflect an entity’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities. The Company elected the fair value option for certain residential mortgage loans held for sale in accordance with ASC 825, Financial Instruments. This election allows for a more effective offset of the changes in fair values of the loans and the derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting under ASC 815, Derivatives and Hedging . The Company has not elected the fair value option for other residential mortgage loans held for sale primarily because they are not economically hedged using derivative instruments. See below and Note 18. Derivative Financial Instruments , for additional information. Assets and Liabilities Measured on a Recurring Basis The following table represents assets and liabilities reported on the consolidated balance sheets at their fair value on a recurring basis as of December 31, 2021 and 2020 by level within the ASC Topic 820 fair value measurement hierarchy: Fair Value Measurements at Reporting Date Using Assets/ Quoted Prices Significant Significant December 31, 2021 Assets: Investment securities available for sale: U.S. treasuries $ 174,996 $ — $ 174,996 $ — Government agency securities 444,675 — 444,675 — Obligations of state and municipal subdivisions 432,760 — 432,760 — Corporate bonds 34,796 — 34,796 — Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 918,550 — 918,550 — Other securities 950 — 950 — Loans held for sale, fair value option elected (1) 28,249 — 28,249 — Derivative financial instruments: Interest rate lock commitments 1,029 — 1,029 — Forward mortgage-backed securities trades 27 — 27 — Loan customer counterparty 6,459 — 6,459 — Financial institution counterparty 1,078 — 1,078 — Liabilities: Derivative financial instruments: Interest rate swaps - cash flow hedge 1,158 — 1,158 — Interest rate lock commitments 4 — 4 — Forward mortgage-backed securities trades 21 — 21 — Loan customer counterparty 1,073 — 1,073 — Financial institution counterparty 6,772 — 6,772 — December 31, 2020 Assets: Investment securities available for sale: U.S. treasuries $ 44,708 $ — $ 44,708 $ — Government agency securities 249,017 — 249,017 — Obligations of state and municipal subdivisions 393,165 — 393,165 — Corporate bonds 22,102 — 22,102 — Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 443,501 — 443,501 — Other securities 1,200 — 1,200 — Loans held for sale, fair value option elected (1) 71,769 — 71,769 — Derivative financial instruments: Interest rate lock commitments 3,515 — 3,515 — Loan customer counterparty 20,159 — 20,159 — Liabilities: Derivative financial instruments: Forward mortgage-backed securities trades 568 — 568 — Financial institution counterparty 21,306 — 21,306 — ____________ (1) At December 31, 2021 and 2020, loans held for sale for which the fair value option was elected had an aggregate outstanding principal balance of $27,176 and $68,670, respectively. There were no mortgage loans held for sale under the fair value option that were 90 days or greater past due or on nonaccrual at December 31, 2021. A description of the valuation methodologies used for instruments measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy, is set forth below. Investment securities Securities classified as available for sale are reported at fair value utilizing Level 1 and Level 2 inputs. Securities are classified within Level 1 when quoted market prices are available in an active market. Inputs include securities that have quoted prices in active markets for identical assets. For securities utilizing Level 2 inputs, the Company obtains fair value measurements from an independent pricing service. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury and other yield curves, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the security’s terms and conditions, among other things. Loans held for sale Certain mortgage loans held for sale are measured at fair value on a recurring basis due to the Company's election to adopt fair value accounting treatment for those loans originated for which the Company has entered into certain derivative financial instruments as part of its mortgage banking and related risk management activities. These instruments include interest rate lock commitments and mandatory forward commitments to sell these loans to investors known as forward mortgage-backed securities trades. This election allows for a more effective offset of the changes in fair values of the assets and the mortgage related derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting under ASC 815, Derivatives and Hedging. Mortgage loans held for sale, for which the fair value option was elected, which are sold on a servicing released basis, are valued using a market approach by utilizing either: (i) the fair value of securities backed by similar mortgage loans, adjusted for certain factors to approximate the fair value of a whole mortgage loan, including the value attributable to mortgage servicing and credit risk, (ii) current commitments to purchase loans or (iii) recent observable market trades for similar loans, adjusted to credit risk and other individual loan characteristics. As these prices are derived from market observable inputs, the Company classifies these valuations as Level 2 in the fair value disclosures. For mortgage loans held for sale for which the fair value option was elected, the earned current contractual interest payment is recognized in interest income, loan origination costs and fees on fair value option loans are recognized in earnings as incurred and not deferred. The Company has no continuing involvement in any residential mortgage loans sold. Derivatives The Company utilizes interest rate swaps to hedge exposure to interest rate risk and variability of cash flows associated to changes in the underlying interest rate of the hedged item. These hedging interest rate swaps are classified as a cash flow hedge. The Company utilizes a third-party vendor for derivative valuation purposes. These vendors determine the appropriate fair value based on a net present value calculation of the cash flows related to the interest rate swaps using primarily observable market inputs such as interest rate yield curves (Level 2 inputs). The estimated fair values of interest rate lock commitments utilize current secondary market prices for underlying loans and estimated servicing value with similar coupons, maturity and credit quality, subject to the anticipated loan funding probability (pull-through rate). The fair value of interest rate lock commitments is subject to change primarily due to changes in interest rates and the estimated pull-through rate. These commitments are classified as Level 2 in the fair value disclosures, as the valuations are based on observable market inputs. Forward mortgage-backed securities trades are exchange-traded or traded within highly active dealer markets. In order to determine the fair value of these instruments, the Company utilized the exchange price or dealer market price for the particular derivative contract; therefore these contracts are classified as Level 2. The estimated fair values are subject to change primarily due to changes in interest rates. The Company also enters into certain interest rate derivative positions. The estimated fair value of these commercial loan interest rate swaps are obtained from a pricing service that provides the swaps' unwind value (Level 2 inputs). See Note 18. Derivative Financial Instruments , for more information. Assets and Liabilities Measured on a Nonrecurring Basis In accordance with ASC Topic 820, certain assets and liabilities are measured at fair value on a nonrecurring basis; that is, the assets and liabilities are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). The following table presents the assets carried on the consolidated balance sheet by caption and by level in the fair value hierarchy at December 31, 2021 and 2020, for which a nonrecurring change in fair value has been recorded: Fair Value Measurements at Reporting Date Using Assets Quoted Prices Significant Significant Period Ended December 31, 2021 Assets: Individually evaluated loans $ 11,204 $ — $ — $ 11,204 $ 3,526 December 31, 2020 Assets: Individually evaluated loans $ 16,903 $ — $ — $ 16,903 $ 13,041 Individually evaluated loans (loans which are not expected to repay all principal and interest amounts due in accordance with the original contractual terms) are measured at an observable market price (if available) or at the fair value of the loan’s underlying collateral (if collateral dependent). Fair value of the loan’s collateral is determined by appraisals or independent valuation, which is then adjusted for the estimated costs related to liquidation of the collateral. Management’s ongoing review of appraisal information may result in additional discounts or adjustments to valuation based upon more recent market sales activity or more current appraisal information derived from properties of similar type and/or locale. In addition, management's discounting criteria may vary for loans secured by non-real estate collateral such as inventory, oil and gas reserves, accounts receivable, equipment or other business assets. Therefore, the Company has categorized its individually evaluated loans as Level 3. Other real estate owned is measured at fair value on a nonrecurring basis (upon initial recognition or subsequent impairment). Other real estate owned is classified within Level 3 of the valuation hierarchy. When transferred from the loan portfolio, other real estate is adjusted to fair value less estimated selling costs and is subsequently carried at the lower of carrying value or fair value less estimated selling costs. The fair value is determined using an external appraisal process, discounted based on internal criteria. Therefore, the Company has categorized its other real estate as Level 3. There was no other real estate owned remeasured during the years ended December 31, 2021 and 2020. In addition, mortgage loans held for sale not recorded under the fair value option are required to be measured at the lower of cost or fair value. The fair value of these loans is based upon binding quotes or bids from third party investors. As of December 31, 2021 and 2020, all mortgage loans held for sale not recorded under the fair value option were recorded at cost. Fair Value of Financial Instruments not Recorded at Fair Value The carrying amount, estimated fair value and the level of the fair value hierarchy of the Company’s financial instruments that are reported at amortized cost on the Company's consolidated balance sheets were as follows at December 31, 2021 and 2020: Fair Value Measurements at Reporting Date Using Carrying Estimated Quoted Prices Significant Significant December 31, 2021 Financial assets: Cash and cash equivalents $ 2,608,444 $ 2,608,444 $ 2,608,444 $ — $ — Certificates of deposit held in other banks 3,245 3,246 — 3,246 — Loans held for sale, at cost 3,875 3,982 — 3,982 — Loans, net 12,290,740 12,415,366 — — 12,415,366 FHLB of Dallas stock and other restricted stock 21,573 21,573 — 21,573 — Accrued interest receivable 49,636 49,636 — 49,636 — Financial liabilities: Deposits 15,553,908 15,553,645 — 15,553,645 — Accrued interest payable 5,301 5,301 — 5,301 — FHLB advances 150,000 128,555 — 128,555 — Other borrowings 283,371 303,250 — 303,250 — Junior subordinated debentures 54,221 45,501 — 45,501 — Off-balance sheet assets (liabilities): Commitments to extend credit — — — — — Standby letters of credit — — — — — December 31, 2020 Financial assets: Cash and cash equivalents $ 1,813,987 $ 1,813,987 $ 1,813,987 $ — $ — Certificates of deposit held in other banks 4,482 4,595 — 4,595 — Loans held for sale, at cost 10,878 11,138 — 11,138 — Loans, net 12,978,238 13,093,698 — — 13,093,698 FHLB of Dallas stock and other restricted stock 20,305 20,305 — 20,305 — Accrued interest receivable 60,581 60,581 — 60,581 — Financial liabilities: Deposits 14,398,927 14,407,596 — 14,407,596 — Accrued interest payable 7,397 7,397 — 7,397 — FHLB advances 375,000 371,175 — 371,175 — Other borrowings 312,175 327,150 — 327,150 — Junior subordinated debentures 54,023 42,624 — 42,624 — Off-balance sheet assets (liabilities): Commitments to extend credit — — — — — Standby letters of credit — — — — — The methods and assumptions used by the Company in estimating fair values of financial instruments as disclosed herein in accordance with ASC Topic 825, Financial Instruments, other than for those measured at fair value on a recurring and nonrecurring basis discussed above, are as follows: Cash and cash equivalents: The carrying amounts of cash and cash equivalents approximate their fair value. Certificates of deposit held in other banks: The fair value of certificates of deposit held in other banks is based upon current market rates. Loans held for sale, at cost: The fair value of loans held for sale is determined based upon commitments on hand from investors. Loans: A discounted cash flow model is used to estimate the fair value of the loans. The discounted cash flow approach models the credit losses directly in the projected cash flows, applying various assumptions regarding credit, interest and prepayment risks for the loans based on loan types, payment types and fixed or variable classifications. Federal Home Loan Bank of Dallas and other restricted stock: The carrying value of restricted securities such as stock in the Federal Home Loan Bank of Dallas and Independent Bankers Financial Corporation approximates fair value. Deposits: The fair values disclosed for demand deposits are, by definition, equal to the amount payable on demand at the reporting date (that is their carrying amounts). The carrying amounts of variable-rate certificates of deposit (CDs) approximate their fair values at the reporting date. Fair values for fixed-rate CDs are estimated using a discounted cash flow calculation that applies interest rates currently being offered on certificates to a schedule of aggregated expected monthly maturities on time deposits. Federal Home Loan Bank advances, line of credit and federal funds purchased: The fair value of advances maturing within 90 days approximates carrying value. Fair value of other advances is based on the Company’s current borrowing rate for similar arrangements. Other borrowings: The estimated fair value approximates carrying value for short-term borrowings. The fair value of private subordinated debentures are based upon prevailing rates on similar debt in the market place. The subordinated debentures that are publicly traded are valued based on indicative bid prices based upon market pricing observations in the current market. Junior subordinated debentures: The fair value of junior subordinated debentures is estimated using discounted cash flow analyses based on the published Bloomberg US Financials BB rated corporate bond index yield. Accrued interest: The carrying amounts of accrued interest approximate their fair values. Off-balance sheet instruments: Fair values for off-balance sheet, credit-related financial instruments are based on fees currently charged to enter into similar agreements, taking into account the remaining terms of the agreements and the counterparties' credit standing. The fair value of commitments is not material.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments The Company accounts for its derivative financial instruments in accordance with ASC Topic 815 which requires all derivative instruments to be carried at fair value on the balance sheet. The Company has designated certain derivative instruments used to manage interest rate risk as hedge relationships with certain assets, liabilities or cash flows being hedged. Certain derivatives used for interest rate risk management are not designated in a hedge relationship and are used for asset and liability management related to the Company's mortgage banking activities and commercial customers' financing needs. All derivatives are carried at fair value in either other assets or other liabilities. Derivative instruments designated in a hedge relationship to mitigate exposure to changes in the fair value of an asset, liability, or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair value hedges. Derivative instruments designated in a hedge relationship to mitigate exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. The Company formally documents the relationship between derivatives and hedged items, as well as the risk-management objective and the strategy for undertaking hedge transactions at the inception of the hedge relationship. This documentation includes linking the fair value or cash flow hedges to the specific assets and liabilities on the balance sheet or the specific firm commitments or forecasted transaction. The Company assesses, both at the hedge's inception and on an ongoing basis, whether the derivative instruments that are used are highly effective in offsetting changes in fair values or cash flows of the hedged items. The Company discontinues hedge accounting when it determines that the derivative is no longer effective in offsetting changes in the fair value or cash flows of the hedged item, the derivative is settled or terminates, a hedged forecasted transaction is no longer probable, a hedged firm commitment is no longer firm, or treatment of the derivative as a hedge is no longer appropriate or intended. The Company's objectives in using interest rate derivatives are to add stability to interest income and to manage its exposure to interest rate movements. To accomplish this objective, the Company uses interest rate swaps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of fixed-rate amounts from a counterparty in exchange for the Company making variable-rate payments over the life of the agreements without exchange of the underlying notional amount. During the second quarter of 2021, the Company entered into two interest rate swap derivatives with an aggregated notional amount of $100,000 that were designated as cash flow hedges. The derivatives are intended to hedge the variable cash flows associated with certain existing variable-interest rate loans and were determined to be effective during the year ended December 31, 2021. For derivatives designated and that qualify as cash flow hedges of interest rate risk, the gain or loss on the derivative is recorded in accumulated other comprehensive income and subsequently reclassified into interest income in the same period that the hedged transaction affects earnings. Amounts of loss recognized in accumulated other comprehensive income related to derivatives was $359, net of tax, and the amounts that were reclassified to interest income as interest payments were received on the Company’s variable-rate loans was $472, net of tax, during and for the year ended December 31, 2021, respectively. During the next twelve months, the Company estimates that $513 will be reclassified as an increase to interest income. Through its mortgage banking division, the Company enters into interest rate lock commitments with consumers to originate mortgage loans at a specified interest rate. These commitments, which contain fixed expiration dates, offer the borrower an interest rate guarantee provided the loan meets underwriting guidelines and closes within the timeframe established by the Company. The Company manages the changes in fair value associated with changes in interest rates related to interest rate lock commitments by using forward sold commitments known as forward mortgage-backed securities trades. These instruments are typically entered into at the time the interest rate lock commitment is made. The Company offers certain derivatives products, primarily interest rate swaps, directly to qualified commercial banking customers to facilitate their risk management strategies. The interest rate swap derivative positions relate to transactions in which the Company enters into an interest rate swap with a customer, while at the same time entering into an offsetting interest rate swap with another financial institution. An interest rate swap transaction allows customers to effectively convert a variable rate loan to a fixed rate. In connection with each swap, the Company agrees to pay interest to the customer on a notional amount at a variable interest rate and receive interest from the customer on a similar notional amount at a fixed interest rate. At the same time, the Company agrees to pay another financial institution the same fixed interest rate on the same notional amount and receive the same variable interest rate on the same notional amount. The following table provides the outstanding notional balances and fair values of outstanding derivative positions at December 31, 2021 and 2020: Outstanding Notional Balance Asset Derivative Liability Derivative December 31, 2021 Derivatives designated as hedging instruments: Interest rate swaps - cash flow hedge $ 100,000 $ — $ 1,158 Derivatives not designated as hedging instruments: Interest rate lock commitments 34,064 1,029 4 Forward mortgage-backed securities trades 30,500 27 21 Commercial loan interest rate swaps: Loan customer counterparty 254,935 6,459 1,073 Financial institution counterparty 254,935 1,078 6,772 December 31, 2020 Derivatives not designated as hedging instruments: Interest rate lock commitments $ 116,795 $ 3,515 $ — Forward mortgage-backed securities trades 104,000 — 568 Commercial loan interest rate swaps: Loan customer counterparty 335,370 20,159 — Financial institution counterparty 335,370 — 21,306 The commercial loan customer counterparty weighted average received and paid interest rates for interest rate swaps outstanding were as follows: Weighted Average Interest Rate December 31, 2021 December 31, 2020 Received Paid Received Paid Loan customer counterparty 4.12 % 2.40 % 4.08 % 2.32 % The credit exposure related to interest rate swaps is limited to the net favorable value of all swaps by each counterparty, which was approximately $7,537 at December 31, 2021. In some cases collateral may be required from the counterparties involved if the net value of the derivative instruments exceeds a nominal amount. Collateral levels are monitored and adjusted on a regular basis for changes in interest rate swap values. At December 31, 2021 and 2020, cash of $20,491 and $23,829 and securities of $3,168 and $6,494 were pledged as collateral for these derivatives, respectively. The Company has entered into credit risk participation agreements with financial institution counterparties for interest rate swaps related to loans in which the Company is either a participant or a lead bank. Risk participation agreements entered into as a participant bank provide credit protection to the financial institution counterparty should the borrower fail to perform on its interest rate derivative contract with that financial institution. The Company is party to one risk participation agreement as a participant bank having a notional amount of $5,121 at December 31, 2021. Risk participation agreements entered into as the lead bank provide credit protection to the Company should the borrower fail to perform on its interest rate derivative contract. The Company is party to one risk participation agreement as the lead bank having a notional amount of $9,348 at December 31, 2021. The changes in the fair value of interest rate lock commitments and the forward sales of mortgage-backed securities are recorded in mortgage banking revenue. These gains and losses were not attributable to instrument-specific credit risk. For interest rate swaps, because the Company acts as an intermediary for our customer, changes in the fair value of the underlying derivative contracts substantially offset each other and do not have a material impact on the results of operations. A summary of derivative activity and the related impact on the consolidated statements of income for the years ended December 31, 2021, 2020 and 2019 was as follows: Income Statement Location Years Ended December 31, 2021 2020 2019 Derivatives designated as hedging instruments Interest rate swaps - cash flow hedges Interest and fees on loans $ 584 $ — $ — Derivatives not designated as hedging instruments Interest rate lock commitments Mortgage banking revenue (2,490) 2,668 25 Forward mortgage-backed securities trades Mortgage banking revenue 574 (505) 163

Stock Awards

Stock Awards	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Stock Awards	Stock Awards The Company grants common stock awards to certain employees of the Company. In April 2013, the Board of Directors adopted the 2013 Equity Incentive Plan (2013 Plan). All stock awards issued under expired plans prior to 2013 are fully vested. Under the 2013 Plan, the Compensation Committee may grant awards to certain employees of the Company in the form of restricted stock, restricted stock rights, restricted stock units, qualified and nonqualified stock options, performance share awards and other equity-based awards. The 2013 Plan, as amended, has 2,300,000 reserved shares of common stock to be awarded by the Company's compensation committee. As of December 31, 2021, there were 1,070,419 shares remaining available for grant for future awards. The shares currently issued under the 2013 Plan are restricted stock awards and performance stock units. Restricted stock awarded to employees vest evenly over the required employment period, generally ranging from one three four Restricted Stock Awards The following table summarizes the activity in nonvested restricted stock awards for the years ended December 31, 2021 and 2020: Restricted Stock Awards Number of Weighted Average Nonvested shares, December 31, 2020 468,800 $ 49.01 Granted during the period 115,463 66.10 Vested during the period (185,447) 51.18 Forfeited during the period (35,265) 50.23 Nonvested shares, December 31, 2021 363,551 $ 53.14 Nonvested shares, December 31, 2019 284,861 $ 58.63 Granted during the period 310,290 43.54 Vested during the period (115,436) 58.08 Forfeited during the period (10,915) 48.37 Nonvested shares, December 31, 2020 468,800 $ 49.01 Compensation expense related to these awards is recorded based on the fair value of the award at the date of grant and totaled $8,984, $8,450 and $7,808 for the years ended December 31, 2021, 2020 and 2019, respectively. Compensation expense is recorded in salaries and employee benefits in the accompanying consolidated statements of income. At December 31, 2021, future compensation expense is estimated to be $12,700 and will be recognized over a remaining weighted average period of 2.22 years. The fair value of common stock awards that vested during the years ended December 31, 2021, 2020 and 2019 was $12,651, $5,602 and $8,725, respectively. The Company has recorded $(691), $243 and $21 in excess tax (benefit) expense on vested restricted stock to income tax expense for the years ended December 31, 2021, 2020 and 2019, respectively. There were no modifications of stock agreements during 2021, 2020 and 2019 that resulted in significant additional incremental compensation costs. At December 31, 2021, the future vesting schedule of the nonvested restricted stock awards is as follows: Number of Shares First year 158,463 Second year 118,975 Third year 77,350 Fourth year 8,763 Total nonvested shares 363,551 Performance Stock Units Performance stock units represent shares potentially issuable in the future. The number of shares issued is based upon the measure of the Company's achievement of its relative adjusted return on average tangible common equity, as defined by the Company, over the award's performance period as compared to an identified peer group's achievement over the same performance period. The number of shares issuable under each performance award is the product of the award target and the award payout percentage for the given level of achievement which ranges from 0% to 150% of the target. The following table summarizes the activity in nonvested performance stock units at target award level for the years ended December 31, 2021 and 2020: Performance-based Restricted Stock Units Number of Weighted Average Nonvested shares, December 31, 2020 89,300 $ 38.29 Granted during the period 25,198 63.92 Nonvested shares, December 31, 2021 114,498 $ 43.93 Nonvested shares, December 31, 2019 — $ — Granted during the period 89,300 38.29 Nonvested shares, December 31, 2020 89,300 $ 38.29 Compensation expense related to performance stock units is estimated each period based on the fair value of the target stock unit at the grant date and the most probable level of achievement of the performance condition, adjusted for the passage of time within the vesting periods of the awards. Compensation expense related to these awards was $1,707 and $0 for the years ended December 31, 2021 and 2020, respectively. As of December 31, 2021, the unrecognized compensation expense assuming the target attainment is estimated to be $3,323, while the estimated maximum payout rate is $5,838 . The remaining performance period over which the expense will be recognized is 2.49 years.

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2021
Regulated Operations [Abstract]
Regulatory Matters	Regulatory Matters Under banking law, there are legal restrictions limiting the amount of dividends the Bank can declare. Approval of the regulatory authorities is required if the effect of dividends declared would cause the regulatory capital of the Bank to fall below specified minimum levels. For state banks, subject to regulatory capital requirements, payment of dividends is generally allowed to the extent of net profits. The Company (on a consolidated basis) and the Bank are subject to various regulatory capital requirements administered by federal and state banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on the Company’s consolidated financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Company and the Bank must meet specific capital guidelines that involve quantitative measures of assets, liabilities and certain off-balance sheet items as calculated under regulatory accounting practices. The capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors. Tier 2 capital for the Company includes permissible portions of the Company's subordinated notes. The permissible portion of qualified subordinated notes decreases 20% per year during the final five years of the term of the notes. The Company is subject to the Basel III regulatory capital framework (the Basel III Capital Rules). The Basel III Capital Rules require that the Company maintain a 2.5% capital conservation buffer above the minimum risk-based capital adequacy requirements. The capital conservation buffer is designed to absorb losses during periods of economic stress and requires increased capital levels for the purpose of capital distributions and other payments. Failure to meet the full amount of the buffer will result in restrictions on the Company's ability to make capital distributions, including dividend payments and stock repurchases and to pay discretionary bonuses to executive officers. As discussed in Note 1. Summary of Significant Accounting Policies , in connection with the adoption of ASC 326, the Company recognized an after-tax cumulative effect reduction to retained earnings of $53,880 on January 1, 2021. In February 2019, the federal bank regulatory agencies issued a final rule that revised certain capital regulations under CECL and included a transition option that allows banking organizations to phase in, over a three-year period, the day-one adverse effects of CECL on their regulatory capital ratios (three-year transition option). The Company elected to adopt the three-year transition option and the deferral has been applied in the December 31, 2021 capital ratios presented below. Quantitative measures established by regulation to ensure capital adequacy require the Company and the Bank to maintain minimum amounts and ratios (set forth in the table below) of total, Common Equity Tier 1 (CET1) and Tier 1 capital (as defined in the regulations) to risk weighted assets (as defined), and of Tier 1 capital (as defined) to average assets (as defined). Management believes, as of December 31, 2021 and 2020, the Company and the Bank meet all capital adequacy requirements to which they are subject, including the capital buffer requirement. As of December 31, 2021 and 2020, the Bank’s capital ratios exceeded those levels necessary to be categorized as “well capitalized” under the regulatory framework for prompt corrective action. To be categorized as “well capitalized,” the Bank must maintain minimum total risk based, CET1, Tier 1 risk based and Tier 1 leverage ratios as set forth in the table. There are no conditions or events that management believes have changed the Bank’s category. The following table presents actual capital amounts and required ratios under Basel III Capital Rules for the Company and Bank as of December 31, 2021 and December 31, 2020. Actual Minimum Capital To Be Well Amount Ratio Amount Ratio Amount Ratio December 31, 2021 Total capital to risk weighted assets: Consolidated $ 1,916,163 13.67 % $ 1,471,510 10.50 % N/A N/A Bank 1,983,530 14.16 1,471,036 10.50 $ 1,400,987 10.00 % Tier 1 capital to risk weighted assets: Consolidated 1,614,372 11.52 1,191,223 8.50 N/A N/A Bank 1,885,739 13.46 1,190,839 8.50 1,120,790 8.00 Common equity tier 1 to risk weighted assets: Consolidated 1,558,772 11.12 981,007 7.00 N/A N/A Bank 1,885,739 13.46 980,691 7.00 910,642 6.50 Tier 1 capital to average assets: Consolidated 1,614,372 8.80 733,954 4.00 N/A N/A Bank 1,885,739 10.28 733,785 4.00 917,231 5.00 December 31, 2020 Total capital to risk weighted assets: Consolidated $ 1,825,661 13.32 % $ 1,438,939 10.50 % N/A N/A Bank 1,864,240 13.61 1,438,385 10.50 $ 1,369,891 10.00 % Tier 1 capital to risk weighted assets: Consolidated 1,471,841 10.74 1,164,855 8.50 N/A N/A Bank 1,776,420 12.97 1,164,407 8.50 1,095,913 8.00 Common equity tier 1 to risk weighted assets: Consolidated 1,416,241 10.33 959,293 7.00 N/A N/A Bank 1,776,420 12.97 958,924 7.00 890,429 6.50 Tier 1 capital to average assets: Consolidated 1,471,841 9.12 645,730 4.00 N/A N/A Bank 1,776,420 11.01 645,539 4.00 806,924 5.00 Stock repurchase program: From time to time, the Company's board of directors has authorized stock repurchase programs which allow the Company to purchase its common stock generally over a one-year period at various prices in the open market or in privately negotiated transactions. On October 22, 2020, the Company's board of directors authorized a $150,000 stock repurchase program allowing the Company to purchase shares of its common stock through October 31, 2021. On August 26, 2021, the Company extended the stock repurchase program through December 31, 2021. Under this program, the Company repurchased 419,098 shares at a total cost of $29,241 for the year ended December 31, 2021, and 109,548 shares at a total cost of $5,660 for the year ended December 31, 2020. In December 2021, upon the expiration of the current plan, the Company's Board established the 2022 Stock Repurchase Plan, which provides for the repurchase of up to $160,000 of common stock through December 31, 2022. Federal bank regulators have adopted final rules that, among other things, eliminated the standalone prior approval requirement for any repurchase of common stock. However, the Company remains subject to a Federal Reserve Board guideline that requires consultation with the Federal Reserve regarding plans for share repurchases. The Company’s repurchases of its common stock may be subject to a prior approval or notice requirement under other regulations, policies or supervisory expectations of the Federal Reserve Board.

Parent Company Only Financial S

Parent Company Only Financial Statements	12 Months Ended
	Dec. 31, 2021
Condensed Financial Information Disclosure [Abstract]
Parent Company Only Financial Statements	Parent Company Only Financial Statements The following balance sheets, statements of income and statements of cash flows for Independent Bank Group, Inc. should be read in conjunction with the consolidated financial statements and the notes thereto. Balance Sheets December 31, Assets 2021 2020 Cash and cash equivalents $ 10,747 $ 5,482 Investment in subsidiaries 2,904,395 2,876,171 Investment in trusts 1,724 1,724 Other assets 3,039 3,849 Total assets $ 2,919,905 $ 2,887,226 Liabilities and Stockholders' Equity Other borrowings $ 283,371 $ 312,175 Junior subordinated debentures 54,221 54,023 Other liabilities 5,663 5,657 Total liabilities 343,255 371,855 Stockholders' equity: Preferred stock — — Common stock 428 431 Additional paid-in capital 1,945,497 1,934,807 Retained earnings 625,484 543,800 Accumulated other comprehensive income 5,241 36,333 Total stockholders' equity 2,576,650 2,515,371 Total liabilities and stockholders' equity $ 2,919,905 $ 2,887,226 Statements of Income Years Ended December 31, 2021 2020 2019 Interest expense: Interest on other borrowings $ 15,247 $ 12,446 $ 11,561 Interest on junior subordinated debentures 1,756 2,162 3,028 Total interest expense 17,003 14,608 14,589 Noninterest income: Dividends from subsidiaries 134,547 83,314 105,877 Other 61 — 1 Total noninterest income 134,608 83,314 105,878 Noninterest expense: Salaries and employee benefits 10,546 8,346 7,653 Professional fees 126 202 264 Acquisition expense, including legal — 16,225 33,445 Other 2,510 2,424 2,562 Total noninterest expense 13,182 27,197 43,924 Income before income tax benefit and equity in undistributed income of subsidiaries 104,423 41,509 47,365 Income tax benefit 7,131 9,410 11,066 Income before equity in undistributed income of subsidiaries 111,554 50,919 58,431 Equity in undistributed income of subsidiaries 113,196 150,290 134,305 Net income $ 224,750 $ 201,209 $ 192,736 Statements of Cash Flows Years Ended December 31, 2021 2020 2019 Cash flows from operating activities: Net income $ 224,750 $ 201,209 $ 192,736 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed net income of subsidiaries (113,196) (150,290) (134,305) Amortization of discount and origination costs on borrowings 894 720 633 Stock based compensation expense 10,691 8,450 7,808 Excess tax (benefit) expense on restricted stock vested (691) 243 21 Deferred tax (benefit) expense (210) 96 2,165 Net change in other assets 1,020 (590) 1,863 Net change in other liabilities 500 (952) (64) Net cash provided by operating activities 123,758 58,886 70,857 Cash flows from investing activities: Capital investment in subsidiaries — (120,000) — Cash acquired in connection with acquisition — — 339 Cash paid in connection with acquisition — — (9) Net cash (used in) provided by investing activities — (120,000) 330 Cash flows from financing activities: Proceeds from other borrowings 75,000 148,653 65,000 Repayments of other borrowings (104,500) (39,250) (40,500) Offering costs paid in connection with acquired bank — — (804) Repurchase of common stock (32,132) (5,819) (51,659) Dividends paid (56,861) (45,265) (43,302) Net cash (used in) provided by financing activities (118,493) 58,319 (71,265) Net change in cash and cash equivalents 5,265 (2,795) (78) Cash and cash equivalents at beginning of year 5,482 8,277 8,355 Cash and cash equivalents at end of year $ 10,747 $ 5,482 $ 8,277

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Declaration of dividends On January 28, 2022, the Company declared a quarterly cash dividend in the amount of $0.38 per share of common stock to the stockholders of record on February 10, 2022. The dividend totaling $16,238 was paid on February 17, 2022. Line of credit agreement On February 16, 2022, the Company's $100,000 unsecured revolving line of credit was renewed and matures on February 16, 2023. The interest rate was amended to the Monthly Reset Bloomberg Short-Term Bank Yield Index (BSBY) plus 1.75%. As of February 25, 2022, the Company has no borrowings against its revolving line of credit.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of presentation: The accompanying consolidated financial statements include the accounts of IBG and all other entities in which IBG has controlling financial interest. All material intercompany transactions and balances have been eliminated in consolidation. In addition, the Company wholly-owns nine statutory business trusts that were formed for the purpose of issuing trust preferred securities and do not meet the criteria for consolidation (See Note 11. Junior Subordinated Debentures ). Accounting standards codification: The Financial Accounting Standards Board's (FASB) Accounting Standards Codification (ASC) is the officially recognized source of authoritative U.S. generally accepted accounting principles (GAAP) applicable to all public and non-public non-governmental entities. Rules and interpretive releases of the SEC under the authority of federal securities laws are also sources of authoritative GAAP for SEC registrants. All other accounting literature is considered non-authoritative.
Segment Reporting	Segment reporting: The Company has one reportable segment. The Company’s chief operating decision-maker uses consolidated results to make operating and strategic decisions.
Reclassifications	Reclassifications: Certain prior period financial statement and disclosure amounts have been reclassified to conform to current period presentation. The reclassifications have no effect on net income or stockholders' equity as previously reported.
Use of estimates	Use of estimates: The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect certain reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Accordingly, actual results could differ from those estimates. The material estimates included in the financial statements relate to the allowance for credit losses, the valuation of goodwill and valuation of assets and liabilities acquired in business combinations.
Cash and cash equivalents	Cash and cash equivalents: For the purposes of reporting cash flows, cash and cash equivalents include cash on hand, amounts due from banks and federal funds sold. All highly liquid investments with an initial maturity of less than ninety days are considered to be cash equivalents. The Company maintains deposits with other financial institutions in amounts that exceed FDIC insurance coverage. The Company's management monitors the balance in these accounts and periodically assesses the financial condition of the other financial institutions. The Company has not experienced any losses in such accounts and believes it is not exposed to any significant credit risks on cash or cash equivalents. Restricted cash: The Company maintains cash collateral balances which have been pledged to derivative counterparties and are legally restricted as to use.
Certificates of deposit	Certificates of deposit: Certificates of deposit are FDIC insured deposits in other financial institutions that mature within 18 months and are carried at cost.
Securities	Securities: Debt securities that management has the positive intent and ability to hold to maturity are classified as held to maturity and recorded at amortized cost. Debt securities that the Company intends to hold for an indefinite period of time, but not necessarily to maturity are classified as available for sale. Securities available for sale are reported at fair value with unrealized gains or losses reported as a separate component of other comprehensive income, net of tax. Any decision to sell a security classified as available for sale would be based on various factors, including significant movements in interest rates, changes in the maturity mix of the Company's assets and liabilities, liquidity needs, regulatory capital considerations and other similar factors. The amortization of premiums and accretion of discounts, computed by the interest method generally over their contractual lives, are recognized in interest income. Premiums on callable securities are amortized to their earliest call date. Realized gains or losses, determined on the basis of the cost of specific securities sold, are included in earnings on the trade date. As of December 31, 2021 and 2020, all of the Company's securities were classified as available for sale.
Loans held for sale	Loans held for sale: The Company originates residential mortgage loans that may subsequently be sold to unaffiliated third parties. The Company elected the fair value option for certain residential mortgage loans held for sale in accordance with ASC 825, Financial Instruments. This election allows for a more effective offset of the changes in fair values of the loans and the derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting under ASC 815, Derivatives and Hedging . The Company has not elected the fair value option for other residential mortgage loans held for sale primarily because they are not economically hedged using derivative instruments. Mortgage loans originated and intended for sale not recorded under the fair value option are carried at the lower of aggregate cost or fair value, as determined by aggregate outstanding commitments from investors. Net unrealized losses, if any, are recognized through a valuation allowance by charges to income. All mortgage loans held for sale are sold without servicing rights retained. Gains and losses on sales of loans are recognized in noninterest income at settlement dates and are determined by the difference between the sales proceeds and the carrying value of the loans.
Loans, net	Loans held for investment: Loans that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off are reported at their outstanding principal balance, net of unearned interest, purchase premiums and discounts, deferred loan fees or costs and an allowance for credit losses. Loan origination fees, net of direct origination costs, are deferred and recognized as an adjustment to the related loan yield using the effective interest method without anticipating prepayments. Further information regarding the Company's accounting policies related to past due loans, non-accrual loans, collateral dependent loans and troubled-debt restructurings is presented in Note 5. Loans, Net and Allowance for Credit Losses on Loans .
Acquired loans	Acquired loans: In accordance with ASC 326, Measurement of Credit Losses on Financial Instruments , loans acquired in connection with a business combination are recorded at their acquisition-date fair value. The allowance for credit losses related to the acquired loan portfolio is not carried over. Acquired loans are classified into two categories based on the credit risk characteristics of the underlying borrowers as either purchased credit deteriorated (PCD) loans, or loans with no evidence of credit deterioration (non-PCD). PCD loans are defined as a loan or pool of loans that have experienced more-than-insignificant credit deterioration since the origination date. For PCD loans, an initial allowance is established on the acquisition date using the same methodology as other loans held for investment and combined with the fair value of the loan to arrive at acquisition date amortized cost. Accordingly, no provision for credit losses is recognized on PCD loans at the acquisition date. Subsequent to the acquisition date, changes to the allowance are recognized in the provision for credit losses. Non-PCD loans are pooled into segments together with originated held for investment loans that share similar risk characteristics and have an allowance established on the acquisition date, which is recognized in the current period provision for credit losses. Determining the fair value of the acquired loans involves estimating the principal and interest payment cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. For PCD loans, the non-credit discount or premium is allocated to individual loans as determined by the difference between the loan’s unpaid principal balance and amortized cost basis. The non-credit premium or discount is recognized into interest income on a level yield basis over the remaining expected life of the loan. For non-PCD loans, the fair value discount or premium is allocated to individual loans and recognized into interest income on a level yield basis over the remaining expected life of the loan. Prior to January 1, 2021 as further discussed in Note 2. Recent Accounting Standards , loans acquired in a business combination that had evidence of credit impairment and for which it was probable, at acquisition, that the Company would be unable to collect all contractually required payments receivable were considered PCI. PCI loans were accounted for individually or aggregated into pools of loans based on common risk characteristics such as credit grade, loan type, and date of origination.
Allowance for Credit Losses on Loans	Allowance for credit losses: Refer to Note 2. Recent Accounting Standards for discussion of the change in methodology used to calculate the allowance for credit losses as a result of adopting of ASU 2016-13, Financial Instruments - Credit Losses (Topic 326), effective January 1, 2021. Allowance for credit losses - loans : In accordance with ASC 326, Measurement of Credit Losses on Financial Instruments , the allowance for credit losses on loans is a valuation account that is deducted from the amortized cost basis of loans to present management's best estimate of the net amount expected to be collected. Loans, or portions thereof, are charged-off against the allowance for credit losses when management believes that collectability of the principal is unlikely. Subsequent recoveries, if any, are credited to the allowance. The allowance is increased (decreased) by provisions (or reversals of) reported in the income statement as a component of provision for credit losses. Management has made the accounting policy election to exclude accrued interest receivable on loans from the estimate of credit losses and reports accrued interest separately in other assets in the consolidated balance sheets. Further information regarding Company policies and methodology used to estimate the allowance for credit losses on loans is presented in Note 5. Loans, Net and Allowance for Credit Losses on Loans . The Company's allowance balance is estimated using relevant available information, from internal and external sources, relating to past events, current conditions and reasonable and supportable forecasts. Historical credit loss experience provides the basis for the estimation of expected credit losses. Adjustments to historical loss information are made for differences in current loan-specific risk characteristics such as differences in underwriting standards, portfolio mix, credit quality, or term as well as for changes in environmental conditions, such as changes in unemployment rates, gross domestic product, property values or other relevant factors. The Company utilizes Moody’s Analytics economic forecast scenarios and assigns probability weighting to those scenarios which best reflect management’s views on the economic forecast. The allowance for credit losses is measured on a collective basis for portfolios of loans when similar risk characteristics exist. Loans that do not share risk characteristics are evaluated for expected credit losses on an individual basis and excluded from the collective evaluation. For determining the appropriate allowance for credit losses on a collective basis, the loan portfolio is segmented into pools based upon similar risk characteristics and a lifetime loss-rate model is utilized. For modeling purposes, loan pools include: commercial and industrial, energy, commercial real estate - construction/land development, commercial real estate - owner occupied, commercial real estate - non-owner occupied, agricultural, residential real estate, HELOCs, single-family interim construction, and consumer. Management periodically reassesses each pool to ensure the loans within the pool continue to share similar characteristics and risk profiles and to determine whether further segmentation is necessary. The measurement of expected credit losses is impacted by loan/borrower attributes and certain macroeconomic variables. Management has determined that they are reasonably able to forecast the macroeconomic variables used in the modeling processes with an acceptable degree of confidence for a total of two years then encompassing a reversion process whereby the forecasted macroeconomic variables are reverted to their historical mean utilizing a rational, systematic basis. Management qualitatively adjusts model results for risk factors that are not considered within the modeling processes but are nonetheless relevant in assessing the expected credit losses within the loan pools. These qualitative factor (Q-Factor) adjustments may increase or decrease management's estimate of expected credit losses by a calculated percentage or amount based upon the estimated level of risk. Loans exhibiting unique risk characteristics and requiring an individual allowance are measured based on 1) the present value of expected future cash flows discounted at the loan's effective interest rate; 2) the loan's observable market price; or 3) the fair value of collateral if the loan is collateral dependent. Substantially all of the Company’s individually evaluated loans are measured at the fair value of the collateral. Management continually evaluates the allowance for credit losses based upon the factors noted above. Should any of the factors considered by management change, the Company’s estimate of credit losses could also change and would affect the level of future provision for credit losses. Portions of the allowance may be allocated for specific credits; however, the entire allowance is available for any credit that, in management’s judgment, should be charged off. While the calculation of the allowance for credit losses utilizes management’s best judgment and all the information available, the adequacy of the allowance for credit losses is dependent on a variety of factors beyond the Company’s control, including, among other things, the performance of the entire loan portfolio, the economy, changes in interest rates and the view of regulatory authorities towards loan classifications.
Allowance for credit losses on securities	Allowance for credit losses - available for sale securities: For available for sale securities in an unrealized loss position, the Company first assesses whether it intends to sell or it is more-likely-than-not that it will be required to sell the securities before recovery of the amortized cost basis. If either of these criteria is met, the securities amortized cost basis is written down to fair value as a current period expense. If either of the above criteria is not met, the Company evaluates whether the decline in fair value is the result of credit losses or other factors. In making this assessment, management may consider various factors including the extent to which fair value is less than amortized cost, performance of any underlying collateral and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected are compared to the amortized cost basis of the security and any excess of the amortized cost basis over the present value of expected cash flows is recorded as an allowance for credit loss, limited to the amount by which the fair value is less than the amortized cost basis. Any impairment not recorded through an allowance for credit loss is recognized in other comprehensive income as a non credit-related impairment. Changes in the allowance for credit losses are recorded as provision for (or reversal of) credit losses. Available for sale securities are charged-off against the allowance or, in the absence of any allowance, written down through income when deemed uncollectible by management or when either of the aforementioned criteria regarding intent or requirement to sell is met. Allowance for credit losses - held to maturity securities : The allowance for credit losses on held to maturity securities is a valuation account that is deducted from the amortized cost basis of held to maturity securities to present management's best estimate of the net amount expected to be collected. Held to maturity securities are charged-off against the allowance when deemed uncollectible by management. Adjustments to the allowance are reported in the income statement as a component of provision for credit losses. Management measures expected credit losses on held to maturity securities on a collective basis by major security type with each type sharing similar risk characteristics and considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. Management has made the accounting policy election to exclude accrued interest receivable on available for sale and held to maturity securities from the estimate of credit losses and report accrued interest separately in other assets in the consolidated balance sheet.
Allowance for credit losses on off-balance-sheet credit exposures	Allowance for credit losses on off-balance sheet credit exposures: The allowance for credit losses on off-balance sheet credit exposures is a liability account, calculated in accordance with ASC 326, representing expected credit losses over the contractual period for which the Company is exposed to credit risk resulting from a contractual obligation to extend credit. No allowance is recognized if we have the unconditional right to cancel the obligation. The allowance is reported as a component of other liabilities in the consolidated balance sheets. Adjustments to the allowance are reported in the income statement as a component of provision for credit losses. Further information regarding Company policies and methodology used to estimate the allowance for credit losses on off-balance sheet credit exposures is presented in Note 14. Off-Balance Sheet Arrangements, Commitments and Contingencies . Loan commitments and related financial instruments: In the ordinary course of business, the Company has entered into certain off-balance sheet financial instruments consisting of commitments to extend credit, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded in the financial statements when they are funded or related fees are incurred or received.
Premises and equipment, net	Premises and equipment, net: Land is carried at cost. Bank premises, furniture and equipment and aircraft are carried at cost, less accumulated depreciation computed principally by the straight-line method over the estimated useful lives of the assets, which range from three Leasehold improvements are carried at cost and are depreciated over the shorter of the estimated useful life or the lease period.
Software	Software: Costs incurred in connection with development or purchase of internal use software and cloud computing arrangements, including in-substance software licenses, are capitalized. Amortization is computed on a straight-line basis over the estimated useful life of the asset, which generally ranges from one
Leases	Leases: The Company's leases are accounted for under ASC Topic 842, Leases . For operating leases with a term greater than one year, the Company recognizes operating right-of-use (ROU) lease assets and operating lease liabilities, which are recorded in other assets and other liabilities, respectively, in the consolidated balance sheets. The Company determines if an arrangement is a lease at inception. Operating ROU lease assets and related liabilities are recognized at commencement date based on the present value of lease payments over the lease term. As the Company's leases do not provide an implicit rate, the Company uses its incremental borrowing rate referenced to the Federal Home Loan Bank Secure Connect advance rates for borrowings of similar terms in determining the present value of lease payments. The operating ROU lease asset also includes any lease pre-payments made and excludes lease incentives. The Company's lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for lease payments is recognized on a straight-line basis over the lease term. The Company has lease agreements with lease and non-lease components, which the Company has elected to account for separately as the non-lease component amounts are readily determinable under most leases.
Long-term assets	Long-term assets: Premises and equipment and other long-term assets are reviewed for impairment when events indicate that their carrying amount may not be recoverable from future undiscounted cash flows. If impaired, the assets are recorded at fair value.
Other real estate owned	Other real estate owned: Real estate properties acquired through, or in lieu of, loan foreclosure are initially recorded at fair value less estimated selling costs at the date of foreclosure, establishing a new cost basis. After foreclosure, valuations are periodically performed by management and the real estate is carried at the lower of carrying amount or fair value less cost to sell.
Goodwill and other intangible assets, net	Goodwill and other intangible assets, net: Goodwill represents the excess of costs over fair value of net assets of businesses acquired. Goodwill is tested for impairment annually on December 31 or on an interim basis if an event triggering impairment may have occurred. On January 1, 2020, ASU 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment became effective for the Company as further explained in Note 2. Recent Accounting Standards . Under the guidance, if a reporting unit’s carrying amount exceeds its fair value, an entity will record an impairment charge based on that difference. As of December 31, 2021, the fair value of the Company’s stock price and calculated market capitalization exceeded its carrying value. Core deposit intangibles and other acquired customer relationship intangibles arising from bank acquisitions are amortized on a straight-line basis over their estimated useful lives of ten years and thirteen years, respectively. Other intangible assets are tested for impairment whenever events or changes in circumstances indicate the carrying amount of the assets may not be recoverable from future undiscounted cash flows.
Restricted stock	Restricted stock : The Bank is a member of the FHLB system. Members are required to own a certain amount of stock based on the level of borrowings and other factors, and may invest in additional amounts. FHLB of Dallas and other restricted stock do not have readily determinable fair values as ownership is restricted and they lack a ready market. As a result, these stocks are carried at cost and evaluated periodically by management for impairment. Both cash and stock dividends are reported as income.
Bank-owned life insurance	Bank-owned life insurance: Bank-owned life insurance is recorded at the amount that can be realized under the insurance contracts at the balance sheet date, which is the cash surrender value adjusted for other charges or other amounts due that are probable at settlement. Changes in the net cash surrender value of the policies, as well as insurance proceeds received are reflected in noninterest income.
Income taxes	Income taxes: Income tax expense is the total of the current year income tax due or refundable and the change in deferred tax assets and liabilities (excluding deferred tax assets and liabilities related to business combinations or components of other comprehensive income). Deferred tax assets and liabilities are the expected future tax amounts for the temporary differences between carrying amounts and tax bases of assets and liabilities, computed using enacted tax rates. The effect of a change in tax rates on deferred assets and liabilities is recognized in income taxes during the period that includes the enactment date. A valuation allowance, if needed, reduces deferred tax assets to the expected amount more likely than not to be realized. Realization of deferred tax assets is dependent upon the level of historical income, prudent and feasible tax planning strategies, reversals of deferred tax liabilities and estimates of future taxable income.
Stock based compensation	Stock based compensation: Compensation cost is recognized for restricted stock awards/stock units issued to employees based on the market price of the Company's common stock on the grant date. Stock-based compensation expense is generally recognized using the straight-line method over the requisite service period for time-based awards. Compensation expense for performance stock units is recognized over the service period of the award based upon the probable number of units expected to vest. The impact of forfeitures of stock-based payment awards on compensation expense is recognized as forfeitures occur.
Transfers of financial assets	Transfers of financial assets: Transfers of financial assets are accounted for as sales, when control over the assets has been relinquished. Control over transferred assets is deemed to be surrendered when the assets have been isolated from the Company, the transferee obtains the right (free of conditions that constrain it from taking advantage of that right) to pledge or exchange the transferred assets, and the Company does not maintain effective control over the transferred assets through an agreement to repurchase them before their maturity.
Advertising costs	Advertising costs: Advertising costs are expensed as incurred.
Business combinations	Business combinations: The Company applies the acquisition method of accounting for business combinations. Under the acquisition method, the acquiring entity in a business combination recognizes 100% of the assets acquired and liabilities assumed at their acquisition date fair values. Management utilizes valuation techniques appropriate for the asset or liability being measured in determining these fair values. Any excess of the purchase price over amounts allocated to assets acquired, including identifiable intangible assets, and liabilities assumed is recorded as goodwill. Where amounts allocated to assets acquired and liabilities assumed is greater than the purchase price, a bargain purchase gain is recognized. Adjustments identified during the measurement period are recognized in the reporting period in which the adjustment amounts are determined. Acquisition-related costs are expensed as incurred.
Comprehensive income	Comprehensive income: Accounting principles generally require that recognized revenue, expenses, gains and losses be included in net income. Although certain changes in assets and liabilities, such as unrealized gains and losses on available for sale securities, are reported as a separate component of the equity section of the balance sheet, such items, along with net income, are components of comprehensive income. Gains and losses on available for sale securities are reclassified to net income as the gains or losses are realized upon sale of the securities. For cash flow hedges, gains and losses on the derivative(s) are recorded in accumulated other comprehensive income and subsequently reclassified into interest income in the same period that the hedged transaction affects earnings.
Fair values of financial instruments	Fair values of financial instruments: Accounting standards define fair value, establish a framework for measuring fair value in GAAP, and require certain disclosures about fair value measurements (see Note 17. Fair Value Measurements ). In general, fair values of financial instruments are based upon quoted market prices, where available. If such quoted market prices are not available, fair value is based upon models that primarily use, as inputs, observable market-based parameters. Valuation adjustments may be made to ensure that financial instruments are recorded at fair value. These adjustments may include amounts to reflect counterparty credit quality and the Company's creditworthiness, among other things, as well as unobservable parameters. Any such valuation adjustments are applied consistently over time. The fair value of an asset or liability is the price that would be received to sell that asset or paid to transfer that liability in an orderly transaction occurring in the principal market (or most advantageous market in the absence of a principal market) for such asset or liability. In estimating fair value, the Company utilizes valuation techniques that are consistent with the market approach, the income approach and/or the cost approach. Such valuation techniques are consistently applied. Inputs to valuation techniques include the assumptions that market participants would use in pricing an asset or liability. ASC Topic 820, Fair Value Measurements and Disclosures , establishes a fair value hierarchy for valuation inputs that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The fair value hierarchy is as follows: Level 1 Inputs – Unadjusted quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. Level 2 Inputs – Inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. These might include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, inputs other than quoted prices that are observable for the asset or liability (such as interest rates, volatilities, prepayment speeds, credit risks, etc.) or inputs that are derived principally from or corroborated by market data by correlation or other means. Level 3 Inputs – Unobservable inputs for determining the fair values of assets or liabilities that reflect an entity’s own assumptions about the assumptions that market participants would use in pricing the assets or liabilities. The Company elected the fair value option for certain residential mortgage loans held for sale in accordance with ASC 825, Financial Instruments. This election allows for a more effective offset of the changes in fair values of the loans and the derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting under ASC 815, Derivatives and Hedging . The Company has not elected the fair value option for other residential mortgage loans held for sale primarily because they are not economically hedged using derivative instruments. See below and Note 18. Derivative Financial Instruments , for additional information. Investment securities Securities classified as available for sale are reported at fair value utilizing Level 1 and Level 2 inputs. Securities are classified within Level 1 when quoted market prices are available in an active market. Inputs include securities that have quoted prices in active markets for identical assets. For securities utilizing Level 2 inputs, the Company obtains fair value measurements from an independent pricing service. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury and other yield curves, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the security’s terms and conditions, among other things. Loans held for sale Certain mortgage loans held for sale are measured at fair value on a recurring basis due to the Company's election to adopt fair value accounting treatment for those loans originated for which the Company has entered into certain derivative financial instruments as part of its mortgage banking and related risk management activities. These instruments include interest rate lock commitments and mandatory forward commitments to sell these loans to investors known as forward mortgage-backed securities trades. This election allows for a more effective offset of the changes in fair values of the assets and the mortgage related derivative instruments used to economically hedge them without the burden of complying with the requirements for hedge accounting under ASC 815, Derivatives and Hedging. Mortgage loans held for sale, for which the fair value option was elected, which are sold on a servicing released basis, are valued using a market approach by utilizing either: (i) the fair value of securities backed by similar mortgage loans, adjusted for certain factors to approximate the fair value of a whole mortgage loan, including the value attributable to mortgage servicing and credit risk, (ii) current commitments to purchase loans or (iii) recent observable market trades for similar loans, adjusted to credit risk and other individual loan characteristics. As these prices are derived from market observable inputs, the Company classifies these valuations as Level 2 in the fair value disclosures. For mortgage loans held for sale for which the fair value option was elected, the earned current contractual interest payment is recognized in interest income, loan origination costs and fees on fair value option loans are recognized in earnings as incurred and not deferred. The Company has no continuing involvement in any residential mortgage loans sold. Derivatives The Company utilizes interest rate swaps to hedge exposure to interest rate risk and variability of cash flows associated to changes in the underlying interest rate of the hedged item. These hedging interest rate swaps are classified as a cash flow hedge. The Company utilizes a third-party vendor for derivative valuation purposes. These vendors determine the appropriate fair value based on a net present value calculation of the cash flows related to the interest rate swaps using primarily observable market inputs such as interest rate yield curves (Level 2 inputs). The estimated fair values of interest rate lock commitments utilize current secondary market prices for underlying loans and estimated servicing value with similar coupons, maturity and credit quality, subject to the anticipated loan funding probability (pull-through rate). The fair value of interest rate lock commitments is subject to change primarily due to changes in interest rates and the estimated pull-through rate. These commitments are classified as Level 2 in the fair value disclosures, as the valuations are based on observable market inputs. Forward mortgage-backed securities trades are exchange-traded or traded within highly active dealer markets. In order to determine the fair value of these instruments, the Company utilized the exchange price or dealer market price for the particular derivative contract; therefore these contracts are classified as Level 2. The estimated fair values are subject to change primarily due to changes in interest rates. The Company also enters into certain interest rate derivative positions. The estimated fair value of these commercial loan interest rate swaps are obtained from a pricing service that provides the swaps' unwind value (Level 2 inputs). See Note 18. Derivative Financial Instruments , for more information. The methods and assumptions used by the Company in estimating fair values of financial instruments as disclosed herein in accordance with ASC Topic 825, Financial Instruments, other than for those measured at fair value on a recurring and nonrecurring basis discussed above, are as follows: Cash and cash equivalents: The carrying amounts of cash and cash equivalents approximate their fair value. Certificates of deposit held in other banks: The fair value of certificates of deposit held in other banks is based upon current market rates. Loans held for sale, at cost: The fair value of loans held for sale is determined based upon commitments on hand from investors. Loans: A discounted cash flow model is used to estimate the fair value of the loans. The discounted cash flow approach models the credit losses directly in the projected cash flows, applying various assumptions regarding credit, interest and prepayment risks for the loans based on loan types, payment types and fixed or variable classifications. Federal Home Loan Bank of Dallas and other restricted stock: The carrying value of restricted securities such as stock in the Federal Home Loan Bank of Dallas and Independent Bankers Financial Corporation approximates fair value. Deposits: The fair values disclosed for demand deposits are, by definition, equal to the amount payable on demand at the reporting date (that is their carrying amounts). The carrying amounts of variable-rate certificates of deposit (CDs) approximate their fair values at the reporting date. Fair values for fixed-rate CDs are estimated using a discounted cash flow calculation that applies interest rates currently being offered on certificates to a schedule of aggregated expected monthly maturities on time deposits. Federal Home Loan Bank advances, line of credit and federal funds purchased: The fair value of advances maturing within 90 days approximates carrying value. Fair value of other advances is based on the Company’s current borrowing rate for similar arrangements. Other borrowings: The estimated fair value approximates carrying value for short-term borrowings. The fair value of private subordinated debentures are based upon prevailing rates on similar debt in the market place. The subordinated debentures that are publicly traded are valued based on indicative bid prices based upon market pricing observations in the current market. Junior subordinated debentures: The fair value of junior subordinated debentures is estimated using discounted cash flow analyses based on the published Bloomberg US Financials BB rated corporate bond index yield. Accrued interest: The carrying amounts of accrued interest approximate their fair values. Off-balance sheet instruments: Fair values for off-balance sheet, credit-related financial instruments are based on fees currently charged to enter into similar agreements, taking into account the remaining terms of the agreements and the counterparties' credit standing. The fair value of commitments is not material.
Derivative financial instruments	Derivative financial instruments: The Company enters into certain derivative financial instruments: interest rate lock commitments, forward mortgage-backed securities trades and interest rate swaps. The accounting for changes in fair value depends on the intended use of the derivative. Changes in fair value of derivatives designated in a qualifying hedge relationship are recorded in accumulated other comprehensive income. Changes in fair value of derivatives not designated in a qualifying hedge relationship are recognized directly in earnings. All derivatives are carried at fair value in either other assets or other liabilities. See Note 18. Derivative Financial Instruments for further information regarding Company policy.
Mortgage banking	Mortgage banking: This revenue category reflects the Company's mortgage production revenue, including fees and income derived from mortgages originated with the intent to sell, gains on sales of mortgage loans and the initial and subsequent changes in the fair value of the mortgage derivatives. Interest earned on mortgage loans is recorded in interest income.
Revenue recognition	Revenue recognition: ASC Topic 606, R evenue from Contracts with Customers (ASC 606) , establishes principles for reporting information about the nature, amount, timing and uncertainty of revenue and cash flows arising from the entity's contracts to provide goods or services to customers. The core principle requires an entity to recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration that it expects to be entitled to receive in exchange for those goods or services recognized as performance obligations are satisfied. The majority of the Company's revenue-generating transactions are not subject to ASC 606, including revenue generated from financial instruments, such as loans, letters of credit, and investment securities, as well as revenue related to mortgage banking activities, and BOLI, as these activities are subject to other accounting guidance. Descriptions of revenue-generating activities that are within the scope of ASC 606, and are presented in the accompanying Consolidated Statements of Income as components of noninterest income, are as follows: • Service charges on deposit accounts - these represent general service fees for monthly account maintenance and activity or transaction-based fees and consist of transaction-based revenue, time-based revenue (service period), item-based revenue or some other individual attribute-based revenue. Revenue is recognized when the performance obligation is completed which is generally monthly for account maintenance services or when a transaction has been completed (such as a wire transfer). Payment for such performance obligations are generally received at the time the performance obligations are satisfied. • Investment management and trust - includes income related to providing investment management and trust services to customers under investment management and trust contracts. Also included are fees received from a third party broker-dealer as part of a revenue-sharing agreement for fees earned from customers that are referred to a third party. The investment management fees and referral fees are billed and paid on a quarterly basis and recognized ratably throughout the quarter as performance obligations are satisfied. • Mortgage warehouse purchase program fees - includes fees for the administration and funding of mortgage loans, as well as renewal and application fees received from mortgage originator customers through our mortgage warehouse purchase program. Revenue related to the warehouse program is recognized when the related loan interest is paid off or upon renewal or application. • Gains/losses on the sale of other real estate owned - generally recognized when the performance obligation is complete which is typically at delivery of control over the property to the buyer at time of each real estate closing. • Other noninterest income - includes the Company's correspondent bank earnings credit, acquired loan recoveries, other deposit fees, and merchant interchange income. The majority of these fees in other noninterest income are not subject to the requirements of ASC 606. The other deposit fees and merchant interchange income are in the scope of ASC 606, and payment for such performance obligations are generally received at the time the performance obligations are satisfied. The Company has made no significant judgments in applying the revenue guidance prescribed in ASC 606 that affect the determination of the amount and timing of revenue from the above-described contracts with customers.
Subsequent events	Subsequent events: Companies are required to evaluate events and transactions that occur after the balance sheet date but before the date the financial statements are issued. They must recognize in the financial statements the effect of all events or transactions that provide additional evidence of conditions that existed at the balance sheet date, including the estimates inherent in the financial statement preparation process. Entities shall not recognize the impact of events or transactions that provide evidence about conditions that did not exist at the balance sheet date but arose after that date. The Company has evaluated subsequent events through the date of filing these financial statements with the Securities and Exchange Commission (SEC) and noted no subsequent events requiring financial statement recognition or disclosure, except as disclosed in Note 22. Subsequent Events .
Earnings per share	Earnings per share: Basic earnings per common share is calculated as net income available to common shareholders divided by the weighted average number of common shares outstanding during the period. The unvested share-based payment awards that contain rights to nonforfeitable dividends are considered participating securities for this calculation. Diluted earnings per common share includes the dilutive effect of additional potential common shares issuable under participating nonvested restricted stock awards as well as performance stock units (PSUs). The participating nonvested restricted stock awards were not included in dilutive shares as they were anti-dilutive for the years ended December 31, 2021, 2020 and 2019. Proceeds from the assumed exercise of dilutive participating nonvested restricted stock awards and PSUs are assumed to be used to repurchase common stock at the average market price.
Recent accounting pronouncements	Adoption of new accounting standards ASU 2016-13, Financial Instruments - Credit Losses (Topic 326) (ASC 326): Measurement of Credit Losses on Financial Instruments (ASU 2016-13). On January 1, 2020, ASU 2016-13, as amended, became effective for the Company. ASU 2016-13 replaces the incurred loss methodology with an expected loss methodology that is referred to as the current expected credit loss (CECL) methodology. The measurement of expected credit losses under the CECL methodology is applicable to financial assets measured at amortized cost, including loan receivables and held to maturity debt securities. It also applies to off-balance sheet credit exposures not accounted for as insurance (loan commitments, standby letters of credit, financial guarantees, and other similar instruments). The CECL model requires the measurement of all expected credit losses on applicable financial assets based on historical experience, current conditions, and reasonable and supportable forecasts. In addition, ASU 2016-13 includes certain changes to the accounting for available for sale securities such as requiring credit-related impairments to be recognized as an allowance for credit losses rather than as a direct write-down of the securities amortized cost basis when management does not intend to sell or believes that it is more likely than not they will be required to sell securities prior to recovery of the securities amortized cost basis. On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (CARES Act) was signed by the President of the United States that included an option for financial institutions to delay the implementation of ASU 2016-13 until the earlier of the termination date of the national emergency declaration by the President or December 31, 2020. On December 27, 2020, the Consolidated Appropriations Act, 2021 (Act 2021), was signed into law which further extended the implementation date of CECL to the earlier of the first day of the entity’s fiscal year that begins after the date on which the COVID-19 national emergency terminates or January 1, 2022. Under the CARES Act provision, the Company elected to delay implementation of ASU 2016-13 and calculated and recorded its provision for credit losses under the incurred loss model that existed prior to ASU 2016-13 for the year ended December 31, 2020. With regard to Act 2021 amendments, the SEC staff indicated it would not object to a registrant early adopting on December 31, 2020, retrospective to January 1, 2020, or January 1, 2021, effective as of January 1, 2021. Under this guidance, the Company elected to adopt ASU 2016-13 with an effective implementation date of January 1, 2021. The Company adopted ASU 2016-13 using the modified retrospective method for all financial assets measured at amortized cost and off-balance sheet credit exposures. As a result of this adoption, the Company recognized a cumulative effect reduction to retained earnings totaling $53,880, net of a recorded deferred tax asset of $15,113, and reclassed $13,035 of allowance for credit loss related to financial assets purchased with credit deterioration (PCD) that were previously classified as purchased credit impaired (PCI) and accounted for under ASC 310-30 as discussed below. Results for periods beginning after January 1, 2021 are presented in accordance with ASU 2016-13 while prior period amounts continue to be reported in accordance with previously applicable GAAP. The Company adopted ASU 2016-13 using the prospective transition approach for PCD assets. In accordance with the standard, management did not reassess whether PCI assets met the criteria of PCD assets as of the date of adoption. On January 1, 2021, the amortized cost basis of the PCD assets were adjusted to reflect the addition of the allowance for credit losses. The remaining noncredit discount (based on the adjusted amortized cost basis) was accreted into interest income at the effective interest rate as of January 1, 2021. The following table illustrates the impact of ASU 2016-13 on the allowances for credit losses as of January 1, 2021, the date of adoption: January 1, 2021 Pre-Adoption Allowance Impact of Adoption Initial allowance on loans purchased with credit deterioration Post-Adoption Allowance Assets: Allowance for credit losses on Loans: Commercial $ 27,311 $ 12,775 $ 4,328 $ 44,414 Commercial real estate 36,698 29,108 7,640 73,446 Commercial construction, land and land development 13,425 22,008 927 36,360 Residential real estate 6,786 (2,255) 140 4,671 Single-family interim construction 2,156 7,179 — 9,335 Agricultural 337 (178) — 159 Consumer 684 (334) — 350 Unallocated 423 (423) — — $ 87,820 $ 67,880 $ 13,035 $ 168,735 Liabilities: Allowance for credit losses on off-balance sheet credit exposures $ — $ 1,113 $ — $ 1,113 ASU 2020-08, Codification Improvements to Subtopic 310-20, Receivables - Nonrefundable Fees and Other Costs . ASU 2020-08 clarifies the accounting for the amortization of purchase premiums for callable debt securities with multiple call dates. ASU 2020-8 was effective for the Company on January 1, 2021 and did not have a significant impact on our financial statements. ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting and subsequent clarifying update ASU 2021-01 Reference Rate Reform (Topic 848); Scope. ASU 2020-04 provides temporary optional guidance to ease the potential burden in accounting for reference rate reform. The new guidance provides optional expedients and exceptions for applying GAAP to contract modifications and hedging relationships, subject to meeting certain criteria, that reference LIBOR or another reference rate expected to be discontinued. The ASU is intended to help stakeholders during the global market-wide reference rate transition period. ASU 2021-01 clarifies that certain optional expedients and exceptions in ASC 848 for contract modifications and hedge accounting apply to derivatives that are affected by the discounting transition. ASU 2021-01 also amends the expedients and exceptions in ASC 848 to capture the incremental consequences of the scope clarification and to tailor the existing guidance to derivative instruments affected by the discounting transition. These ASUs were effective upon issuance and generally can be applied through December 31, 2022. The adoption of these ASUs did not significantly impact our financial statements or disclosures. ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes. The guidance issued in this update simplified the accounting for income taxes by eliminating certain exceptions to the guidance in ASC 740 related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition for deferred tax liabilities for outside basis differences. ASU 2019-12 also simplified aspects of the accounting for franchise taxes and enacted changes in tax laws or rates and clarified the accounting for transactions that result in a step-up in the tax basis of goodwill. ASU 2019-12 was effective for the Company on January 1, 2021 and did not have a significant impact on our financial statements. ASU 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40) - Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract. This ASU aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by these amendments. This ASU became effective for the Company on January 1, 2020 and did not have a significant impact on its financial statements and disclosures. ASU 2018-13, Fair Value Measurement (Topic 820) - Changes to the Disclosure Requirements for Fair Value Measurement. This ASU modified the disclosure requirements on fair value measurements by requiring that Level 3 fair value disclosures include the range and weighted average of significant unobservable inputs used to develop those fair value measurements. For certain unobservable inputs, an entity may disclose other quantitative information in lieu of the weighted average if the entity determines that other quantitative information would be a more reasonable and rational method to reflect the distribution of unobservable inputs used to develop Level 3 fair value measurements. ASU 2018-13 became effective for the Company on January 1, 2020 and did not have a significant impact on its financial statements and disclosures. ASU 2017-08, Receivables - Nonrefundable Fees and Other Costs (Subtopic 310-20), Premium Amortization on Purchased Callable Debt Securities . This ASU requires certain premiums on callable debt securities to be amortized to the earliest call date. The amortization period for callable debt securities purchased at a discount is not impacted. Under current GAAP, premiums on callable debt securities are generally amortized over the contractual life of the security. ASU 2017-08 became effective for the Company on January 1, 2019 and, upon adoption, the Company recognized a cumulative effect adjustment reducing retained earnings by $856, net of the deferred tax impact, but otherwise did not have a significant impact to the Company's consolidated financial statements and disclosures. ASU 2017-04, Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment. This ASU simplified the accounting for goodwill impairment for all entities by requiring impairment charges to be based on the first step in today’s two-step impairment test. Under the guidance, if a reporting unit’s carrying amount exceeds its fair value, an entity will record an impairment charge based on that difference. The impairment charge will be limited to the amount of goodwill allocated to that reporting unit. The standard eliminated the prior requirement to calculate a goodwill impairment charge using Step 2, which required an entity to calculate any impairment charge by comparing the implied fair value of goodwill with its carrying amount. ASU 2017-04 became effective for the Company on January 1, 2020, and did not have a significant impact on its financial statements. ASU 2016-02, Leases (Topic 842)
Mortgage warehouse purchase loans	The Company has a mortgage warehouse purchase program providing mortgage inventory financing for residential mortgage loans originated by mortgage banker clients across a broad geographic scale. Proceeds from the sale of mortgages is the primary source of repayment for warehouse inventory financing via approved investor takeout commitments. These loans typically have a very short duration ranging between a few days to 15 days. In some cases, loans to larger mortgage originators may be financed for up to 60 days. Warehouse purchase program loans are collectively evaluated for impairment and are purchased under several contractual requirements, providing safeguards to the Company. To date, the Company has not experienced a loss on these loans and no allowance for credit losses has been allocated to them.
Loan charge off amounts	The Company will charge-off that portion of any loan which management considers a loss. Commercial and real estate loans are generally considered for charge-off when exposure beyond collateral coverage is apparent and when no further collection of the loss portion is anticipated based on the borrower’s financial condition.
Nonaccrual loan and lease status	The accrual of interest is discontinued on a loan when management believes that, after considering collection efforts and other factors, the borrower's financial condition is such that collection of interest is doubtful, as well as when required by regulatory provisions. Regulatory provisions would typically require the placement of a loan on non-accrual status if 1) principal or interest has been in default for a period of 90 days or more unless the loan is both well secured and in the process of collection or 2) full payment of principal and interest is not expected. All interest accrued but not collected for loans that are placed on nonaccrual status or charged-off is reversed against interest income. Cash collections on nonaccrual loans are generally credited to the loan receivable balance, and no interest income is recognized on those loans until the principal balance has been collected. Loans are generally returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured.
Trouble debt restructuring	The restructuring of a loan is considered a “troubled debt restructuring” (TDR) if both 1) the borrower is experiencing financial difficulties and 2) the creditor has granted a concession. Concessions may include interest rate reductions or below market interest rates, principal forgiveness, extending amortization and other actions intended to minimize potential losses. Modifications primarily relate to extending the amortization periods of the loans and interest rate concessions.
Loans past due	Loans are considered past due if the required principal and interest payments have not been received as of the date such payments were due.
Share repurchase plan	Stock repurchase program: From time to time, the Company's board of directors has authorized stock repurchase programs which allow the Company to purchase its common stock generally over a one-year period at various prices in the open market or in privately negotiated transactions. On October 22, 2020, the Company's board of directors authorized a $150,000 stock repurchase program allowing the Company to purchase shares of its common stock through October 31, 2021. On August 26, 2021, the Company extended the stock repurchase program through December 31, 2021. Under this program, the Company repurchased 419,098 shares at a total cost of $29,241 for the year ended December 31, 2021, and 109,548 shares at a total cost of $5,660 for the year ended December 31, 2020. In December 2021, upon the expiration of the current plan, the Company's Board established the 2022 Stock Repurchase Plan, which provides for the repurchase of up to $160,000 of common stock through December 31, 2022. Federal bank regulators have adopted final rules that, among other things, eliminated the standalone prior approval requirement for any repurchase of common stock. However, the Company remains subject to a Federal Reserve Board guideline that requires consultation with the Federal Reserve regarding plans for share repurchases. The Company’s repurchases of its common stock may be subject to a prior approval or notice requirement under other regulations, policies or supervisory expectations of the Federal Reserve Board.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Earnings Per Share	The following table presents a reconciliation of net income available to common shareholders and the number of shares used in the calculation of basic and diluted earnings per common share. Years Ended December 31, 2021 2020 2019 Basic earnings per share: Net income $ 224,750 $ 201,209 $ 192,736 Less: Undistributed earnings allocated to participating securities 1,576 1,311 971 Dividends paid on participating securities 534 380 281 Net income available to common shareholders $ 222,640 $ 199,518 $ 191,484 Weighted average basic shares outstanding 42,666,007 42,754,606 42,964,393 Basic earnings per share $ 5.22 $ 4.67 $ 4.46 Diluted earnings per share: Net income available to common shareholders $ 222,640 $ 199,518 $ 191,484 Total weighted average basic shares outstanding 42,666,007 42,754,606 42,964,393 Add dilutive performance stock units 58,785 — — Total weighted average diluted shares outstanding 42,724,792 42,754,606 42,964,393 Diluted earnings per share $ 5.21 $ 4.67 $ 4.46 Anti-dilutive participating securities 181,016 58,359 73,546

Accounting Policies (Tables)

Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Accounting Standards Update and Change in Accounting Principle	The following table illustrates the impact of ASU 2016-13 on the allowances for credit losses as of January 1, 2021, the date of adoption: January 1, 2021 Pre-Adoption Allowance Impact of Adoption Initial allowance on loans purchased with credit deterioration Post-Adoption Allowance Assets: Allowance for credit losses on Loans: Commercial $ 27,311 $ 12,775 $ 4,328 $ 44,414 Commercial real estate 36,698 29,108 7,640 73,446 Commercial construction, land and land development 13,425 22,008 927 36,360 Residential real estate 6,786 (2,255) 140 4,671 Single-family interim construction 2,156 7,179 — 9,335 Agricultural 337 (178) — 159 Consumer 684 (334) — 350 Unallocated 423 (423) — — $ 87,820 $ 67,880 $ 13,035 $ 168,735 Liabilities: Allowance for credit losses on off-balance sheet credit exposures $ — $ 1,113 $ — $ 1,113

Statement of Cash Flows (Tables

Statement of Cash Flows (Tables)	12 Months Ended
	Dec. 31, 2021
Supplemental Cash Flow Elements [Abstract]
Other Supplemental Cash Flow Information	Other supplemental cash flow information is presented below: Years Ended December 31, 2021 2020 2019 Cash transactions: Interest expense paid $ 65,336 $ 97,246 $ 144,775 Income taxes paid $ 58,083 $ 54,842 $ 40,504 Noncash transactions: Deferred dividend equivalents $ 197 $ — $ — Transfers of loans to other real estate owned $ — $ 5,239 $ 544 Loans to facilitate the sale of other real estate owned $ — $ 2,039 $ 517 Securities purchased, not yet settled $ — $ — $ 9,975 Transfers of loans held for investment to loans held for sale $ — $ — $ 83,526 Right-of-use assets obtained in exchange for lease liabilities $ 5,156 $ 105 $ 35,553 Loans purchased, not yet settled $ 29,332 $ 9,442 $ — Transfer of bank premises to other real estate $ — $ — $ 7,896 Transfer of repurchase agreements to deposits $ — $ — $ 8,475 Supplemental schedule of noncash investing activities from a branch sale during 2019 is as follows: Year ended December 31, 2019 Noncash assets transferred: Loans, including accrued interest $ 796 Premises and equipment 94 Other assets 2 Total assets $ 892 Noncash liabilities transferred: Deposits, including interest $ 27,721 Other liabilities 27 Total liabilities $ 27,748 Cash and cash equivalents transferred in branch sales $ 206 Deposit premium received $ 1,386 Cash paid to buyer, net of deposit premium $ 24,957 Supplemental schedule of noncash investing activities from sale of trust business during 2019 is as follows: Year ended December 31, 2019 Noncash assets transferred: Customer relationship intangible assets, net $ 2,939 Other assets 11 Total assets $ 2,950 Net cash received from sale $ 4,269 Supplemental schedule of noncash investing activities from an acquisition during 2019 is as follows: Year ended December 31, 2019 Noncash assets acquired Certificates of deposit held in other banks $ 262 Securities available for sale 561,052 Restricted stock 27,794 Loans 2,789,868 Premises and equipment 65,786 Other real estate owned 1,829 Goodwill 272,224 Other intangible assets 71,518 Bank owned life insurance 80,837 Other assets 31,987 Total assets acquired $ 3,903,157 Noncash liabilities assumed: Deposits $ 3,108,810 Repurchase agreements 8,475 FHLB advances 142,653 Other borrowings 40,000 Junior subordinated debentures 25,774 Other liabilities 15,477 Total liabilities assumed $ 3,341,189 Cash and cash equivalents acquired from acquisitions $ 39,913 Cash paid to shareholders of acquired banks $ 9 Fair value of common stock issued to shareholders of acquired banks $ 601,872

Securities Available for Sale (

Securities Available for Sale (Tables)	12 Months Ended
	Dec. 31, 2021
Debt Securities, Available-for-sale [Abstract]
Amortized Cost of Securities and Approximate Fair Values	The amortized cost of securities and their approximate fair values at December 31, 2021 and 2020, are as follows: Amortized Cost (1) Gross Gross Fair Securities Available for Sale December 31, 2021 U.S. treasuries $ 174,950 $ 724 $ (678) $ 174,996 Government agency securities 453,402 1,221 (9,948) 444,675 Obligations of state and municipal subdivisions 418,554 15,440 (1,234) 432,760 Corporate bonds 33,994 862 (60) 34,796 Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 917,942 10,757 (10,149) 918,550 Other securities 950 — — 950 $ 1,999,792 $ 29,004 $ (22,069) $ 2,006,727 December 31, 2020 U.S. treasuries $ 43,060 $ 1,648 $ — $ 44,708 Government agency securities 247,764 3,169 (1,916) 249,017 Obligations of state and municipal subdivisions 373,017 20,168 (20) 393,165 Corporate bonds 21,496 608 (2) 22,102 Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 421,916 21,678 (93) 443,501 Other securities 1,200 — — 1,200 $ 1,108,453 $ 47,271 $ (2,031) $ 1,153,693 ____________ (1) Excludes accrued interest receivable of $8,581 and $6,242 at December 31, 2021 and December 31, 2020, respectively, that is recorded in other assets on the accompanying consolidated balance sheets
Proceeds from Sale, Gross Gains and Losses of Securities Available for Sale	Proceeds from sale of securities available for sale and gross gains and gross losses for the years ended December 31, 2021, 2020 and 2019 were as follows: Years Ended December 31, 2021 2020 2019 Proceeds from sale $ 9,294 $ 13,862 $ 192,417 Gross gains $ 13 $ 385 $ 306 Gross losses $ — $ 3 $ 31
Amortized Cost and Estimated Fair Value of Securities Available for Sale by Contractual Maturity	The amortized cost and estimated fair value of securities available for sale at December 31, 2021, by contractual maturity, are shown below. Maturities of mortgage-backed securities will differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties. December 31, 2021 Securities Available for Sale Amortized Cost (1) Fair Due in one year or less $ 31,164 $ 31,526 Due from one year to five years 198,803 202,479 Due from five to ten years 460,251 459,017 Thereafter 391,632 395,155 1,081,850 1,088,177 Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 917,942 918,550 $ 1,999,792 $ 2,006,727 ____________ (1) Excludes accrued interest receivable of $8,581 at December 31, 2021 that is recorded in other assets on the accompanying consolidated balance sheets
Summary of Unrealized Losses and Fair Value Securities in Continuous Unrealized Loss Position	The number of securities, unrealized losses and fair value, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, as of December 31, 2021 and 2020, are summarized as follows: Less Than 12 Months Greater Than 12 Months Total Description of Securities Number of Securities Estimated Unrealized Number of Securities Estimated Unrealized Estimated Unrealized Securities Available for Sale December 31, 2021 U.S. treasuries 22 $ 144,172 $ (678) — $ — $ — $ 144,172 $ (678) Government agency securities 38 258,334 (4,622) 22 119,963 (5,326) 378,297 (9,948) Obligations of state and municipal subdivisions 14 47,200 (988) 2 3,555 (246) 50,755 (1,234) Corporate bonds 3 13,440 (60) — — — 13,440 (60) Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 115 621,717 (8,471) 11 44,620 (1,678) 666,337 (10,149) 192 $ 1,084,863 $ (14,819) 35 $ 168,138 $ (7,250) $ 1,253,001 $ (22,069) December 31, 2020 Government agency securities 20 112,897 (1,916) — — — 112,897 (1,916) Obligations of state and municipal subdivisions 2 3,786 (20) — — — 3,786 (20) Corporate bonds 1 998 (2) — — — 998 (2) Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 10 41,344 (93) — — — 41,344 (93) 33 $ 159,025 $ (2,031) — $ — $ — $ 159,025 $ (2,031)

Loans, Net and Allowance for _2

Loans, Net and Allowance for Credit Losses on Loans (Tables)	12 Months Ended
	Dec. 31, 2021
Receivables [Abstract]
Compositions of Loans	Loans, net at December 31, 2021 and 2020, consisted of the following: December 31, 2021 2020 Commercial $ 1,983,886 $ 2,448,699 Mortgage warehouse purchase loans 788,848 1,453,797 Real estate: Commercial 6,617,455 6,096,676 Commercial construction, land and land development 1,180,181 1,245,801 Residential 1,300,122 1,352,465 Single-family interim construction 380,627 326,575 Agricultural 106,512 85,014 Consumer 81,815 67,068 Total loans (1)(2) 12,439,446 13,076,095 Deferred loan fees, net (1) — (10,037) Allowance for credit losses (148,706) (87,820) Total loans, net (2) $ 12,290,740 $ 12,978,238 ____________ (1) Loan class amounts are shown at amortized cost, net of deferred loan fees of $9,406, in accordance with ASC 326 at December 31, 2021 and shown at recorded investment at December 31, 2020.
Summary of Activity in Allowance for Loan Losses by Loan Class	The following is a summary of the activity in the allowance for credit losses on loans by class for the years ended December 31, 2021, 2020 and 2019: Commercial Commercial Real Estate Commercial Construction, Residential Single-Family Agricultural Consumer Unallocated Total Year ended December 31, 2021 Balance at beginning of year $ 27,311 $ 36,698 $ 13,425 $ 6,786 $ 2,156 $ 337 $ 684 $ 423 $ 87,820 Impact of adopting ASC 326 12,775 29,108 22,008 (2,255) 7,179 (178) (334) (423) 67,880 Initial allowance on loans purchased with credit deterioration 4,328 7,640 927 140 — — — — 13,035 Provision for credit losses 12,130 (7,961) (12,373) (2,486) (2,113) (53) 247 — (12,609) Charge-offs (6,856) (375) (126) — — — (174) — (7,531) Recoveries 59 — — 7 — — 45 — 111 Balance at end of year $ 49,747 $ 65,110 $ 23,861 $ 2,192 $ 7,222 $ 106 $ 468 $ — $ 148,706 Year ended December 31, 2020 Balance at beginning of year $ 12,844 $ 24,371 $ 8,714 $ 3,678 $ 1,606 $ 332 $ 231 $ (315) $ 51,461 Provision for credit losses 20,025 13,058 4,711 3,108 632 5 716 738 42,993 Charge-offs (5,670) (735) — — (82) — (386) — (6,873) Recoveries 112 4 — — — — 123 — 239 Balance at end of year $ 27,311 $ 36,698 $ 13,425 $ 6,786 $ 2,156 $ 337 $ 684 $ 423 $ 87,820 Year ended December 31, 2019 Balance at beginning of year $ 11,793 $ 21,343 $ 6,452 $ 3,320 $ 1,402 $ 241 $ 189 $ 62 $ 44,802 Provision for credit losses 8,670 3,027 2,262 498 207 91 427 (377) 14,805 Charge-offs (7,709) (3) — (140) (3) — (509) — (8,364) Recoveries 90 4 — — — — 124 — 218 Balance at end of year $ 12,844 $ 24,371 $ 8,714 $ 3,678 $ 1,606 $ 332 $ 231 $ (315) $ 51,461
Individually Evaluated Loans	The following table presents loans that were evaluated for expected credit losses on an individual basis and the related specific credit loss allocations, by loan class as of December 31, 2021 and December 31, 2020: December 31, 2021 December 31, 2020 Loan Balance - Specific Allocations Loan Balance - Specific Allocations Commercial $ 38,911 $ 15,958 $ 39,298 $ 8,281 Commercial real estate 24,683 1,553 21,848 243 Commercial construction, land and land development 1,350 562 32 — Residential real estate — — 2,550 — Single-family Interim construction — — — — Agricultural — — 613 — Consumer — — 42 — $ 64,944 $ 18,073 $ 64,383 $ 8,524
Summary of Nonperforming Loans by Loan Class	Nonperforming loans by loan class at December 31, 2021 (at amortized cost) and December 31, 2020 (at recorded investment), are summarized as follows: Commercial Commercial Construction, Residential Real Estate Single-Family Agricultural Consumer Total December 31, 2021 Nonaccrual loans (1) $ 36,802 $ 15,218 $ 23 $ 1,592 $ — $ — $ 38 $ 53,673 Loans past due 90 days and still accruing 187 — — 1,603 — — — 1,790 Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing) — 1,714 — 161 — — — 1,875 $ 36,989 $ 16,932 $ 23 $ 3,356 $ — $ — $ 38 $ 57,338 December 31, 2020 (2) Nonaccrual loans $ 25,898 $ 20,040 $ 32 $ 2,372 $ — $ 613 $ 42 $ 48,997 Loans past due 90 days and still accruing 433 — — — — — — 433 Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing) — 1,808 — 178 — — — 1,986 $ 26,331 $ 21,848 $ 32 $ 2,550 $ — $ 613 $ 42 $ 51,416 ____________ (1) There is one nonaccrual loan totaling $18 without an allowance for credit loss as of December 31, 2021. Additionally, no interest income was recognized on nonaccrual loans. No significant amounts of accrued interest was reversed during the year ended December 31, 2021. (2) Excluded loans acquired with deteriorated credit quality under prior GAAP
Summary of Troubled Debt Restructurings	Following is a summary of loans modified under troubled debt restructurings during the years ended December 31, 2021 and 2020: Commercial Commercial Commercial Construction, Residential Single-Family Agricultural Consumer Total Troubled debt restructurings during the year ended December 31, 2021 Number of contracts 2 — — — — — 1 3 Pre-restructuring outstanding recorded investment $ 1,789 $ — $ — $ — $ — $ — $ 6 $ 1,795 Post-restructuring outstanding recorded investment $ 570 $ — $ — $ — $ — $ — $ 6 $ 576 Troubled debt restructurings during the year ended December 31, 2020 Number of contracts — 1 — — — — — 1 Pre-restructuring outstanding recorded investment $ — $ 1,517 $ — $ — $ — $ — $ — $ 1,517 Post-restructuring outstanding recorded investment $ — $ 1,517 $ — $ — $ — $ — $ — $ 1,517
Aging of Past Due Loans by Loan Class	The following table presents information regarding the aging of past due loans by loan class as of December 31, 2021 (at amortized cost) and as of December 31, 2020 (at recorded investment): Loans Loans Total Past Current Total December 31, 2021 Commercial $ 1,041 $ 11,056 $ 12,097 $ 1,971,789 $ 1,983,886 Mortgage warehouse — — — 788,848 788,848 Commercial real estate 2,861 11,784 14,645 6,602,810 6,617,455 Commercial construction, land and land development — — — 1,180,181 1,180,181 Residential real estate 3,838 1,913 5,751 1,294,371 1,300,122 Single-family interim construction 1,290 — 1,290 379,337 380,627 Agricultural 16 — 16 106,496 106,512 Consumer 216 9 225 81,590 81,815 $ 9,262 $ 24,762 $ 34,024 $ 12,405,422 $ 12,439,446 December 31, 2020 (1) Commercial $ 3,243 $ 13,227 $ 16,470 $ 2,393,013 $ 2,409,483 Mortgage warehouse — — — 1,453,797 1,453,797 Commercial real estate 2,434 16,790 19,224 5,921,723 5,940,947 Commercial construction, land and land development 19 — 19 1,230,524 1,230,543 Residential real estate 5,169 1,028 6,197 1,341,587 1,347,784 Single-family interim construction — — — 326,575 326,575 Agricultural — 1 1 84,896 84,897 Consumer 86 41 127 67,156 67,283 10,951 31,087 42,038 12,819,271 12,861,309 Acquired with deteriorated credit quality 624 3,219 3,843 210,943 214,786 $ 11,575 $ 34,306 $ 45,881 $ 13,030,214 $ 13,076,095 ____________ (1) Presented under prior GAAP
Summary of Loans by Credit Quality Indicator by Class	The following summarizes the amortized cost basis of loans by year of origination/renewal and credit quality indicator by class of loan as of December 31, 2021: Revolving Loans Converted to Term Loans Term Loans by Year of Origination or Renewal Revolving Loans December 31, 2021 2021 2020 2019 2018 2017 Prior Total Commercial Pass $ 422,810 $ 183,433 $ 98,059 $ 78,357 $ 81,620 $ 255,213 $ 690,242 $ 5,231 $ 1,814,965 Pass/Watch 260 3,010 1,019 3,135 11,688 65 18,768 3,319 41,264 Special Mention 1,411 117 8,517 7,244 195 4,571 12,885 — 34,940 Substandard 30,277 605 16,041 94 2,478 18,331 13,006 1,988 82,820 Doubtful — — — — — — 9,897 — 9,897 Total commercial $ 454,758 $ 187,165 $ 123,636 $ 88,830 $ 95,981 $ 278,180 $ 744,798 $ 10,538 $ 1,983,886 Mortgage warehouse Pass $ 788,848 $ — $ — $ — $ — $ — $ — $ — $ 788,848 Pass/Watch — — — — — — — — — Special Mention — — — — — — — — — Substandard — — — — — — — — — Doubtful — — — — — — — — — Total mortgage warehouse $ 788,848 $ — $ — $ — $ — $ — $ — $ — $ 788,848 Commercial real estate Pass $ 2,181,292 $ 1,198,508 $ 830,902 $ 645,470 $ 504,126 $ 626,292 $ 71,850 $ 4,320 $ 6,062,760 Pass/Watch 54,671 18,591 39,045 60,955 30,196 74,762 752 1,319 280,291 Special Mention 56,142 16,770 37,331 29,962 17,649 20,100 — — 177,954 Substandard 36,263 16,118 1,136 11,901 281 29,686 1,065 — 96,450 Doubtful — — — — — — — — — Total commercial real estate $ 2,328,368 $ 1,249,987 $ 908,414 $ 748,288 $ 552,252 $ 750,840 $ 73,667 $ 5,639 $ 6,617,455 Revolving Loans Converted to Term Loans Term Loans by Year of Origination or Renewal Revolving Loans December 31, 2021 2021 2020 2019 2018 2017 Prior Total Commercial construction, land and land development Pass $ 618,288 $ 262,136 $ 98,007 $ 85,596 $ 13,751 $ 14,939 $ 18,586 $ — $ 1,111,303 Pass/Watch 17,899 10,459 6,869 — — 84 — — 35,311 Special Mention 3,780 — — — 1,909 — — — 5,689 Substandard 11,601 — 387 14,489 28 1,373 — — 27,878 Doubtful — — — — — — — — — Total commercial construction, land and land development $ 651,568 $ 272,595 $ 105,263 $ 100,085 $ 15,688 $ 16,396 $ 18,586 $ — $ 1,180,181 Residential real estate Pass $ 408,402 $ 267,147 $ 190,890 $ 114,616 $ 88,295 $ 149,871 $ 60,212 $ 2,344 $ 1,281,777 Pass/Watch 1,019 487 1,270 405 2,331 4,179 169 — 9,860 Special Mention 657 — 568 129 250 1,043 126 — 2,773 Substandard 640 369 384 519 774 2,974 52 — 5,712 Doubtful — — — — — — — — — Total residential real estate $ 410,718 $ 268,003 $ 193,112 $ 115,669 $ 91,650 $ 158,067 $ 60,559 $ 2,344 $ 1,300,122 Single-family interim construction Pass $ 305,267 $ 59,584 $ 2,801 $ 312 $ — $ — $ 12,663 $ — $ 380,627 Pass/Watch — — — — — — — — — Special Mention — — — — — — — — — Substandard — — — — — — — — — Doubtful — — — — — — — — — Total single-family interim construction $ 305,267 $ 59,584 $ 2,801 $ 312 $ — $ — $ 12,663 $ — $ 380,627 Agricultural Pass $ 36,442 $ 15,005 $ 4,454 $ 8,033 $ 12,229 $ 4,773 $ 18,993 $ — $ 99,929 Pass/Watch — 526 1,462 52 1,035 — 3,502 — 6,577 Special Mention — — — — — — — — — Substandard — — — — — 6 — — 6 Doubtful — — — — — — — — — Total agricultural $ 36,442 $ 15,531 $ 5,916 $ 8,085 $ 13,264 $ 4,779 $ 22,495 $ — $ 106,512 Consumer Pass $ 10,568 $ 9,496 $ 2,706 $ 710 $ 308 $ 181 $ 57,744 $ 43 $ 81,756 Pass/Watch — — — — 1 — — — 1 Special Mention — — — — — — — — — Substandard 30 2 — — 9 17 — — 58 Doubtful — — — — — — — — — Total consumer $ 10,598 $ 9,498 $ 2,706 $ 710 $ 318 $ 198 $ 57,744 $ 43 $ 81,815 Revolving Loans Converted to Term Loans Term Loans by Year of Origination or Renewal Revolving Loans December 31, 2021 2021 2020 2019 2018 2017 Prior Total Total loans Pass $ 4,771,917 $ 1,995,309 $ 1,227,819 $ 933,094 $ 700,329 $ 1,051,269 $ 930,290 $ 11,938 $ 11,621,965 Pass/Watch 73,849 33,073 49,665 64,547 45,251 79,090 23,191 4,638 373,304 Special Mention 61,990 16,887 46,416 37,335 20,003 25,714 13,011 — 221,356 Substandard 78,811 17,094 17,948 27,003 3,570 52,387 14,123 1,988 212,924 Doubtful — — — — — — 9,897 — 9,897 Total loans $ 4,986,567 $ 2,062,363 $ 1,341,848 $ 1,061,979 $ 769,153 $ 1,208,460 $ 990,512 $ 18,564 $ 12,439,446 A summary of loans at recorded investment by credit quality indicator by class presented under prior GAAP as of December 31, 2020, is as follows: Pass Pass/ Special Mention Substandard Doubtful Total December 31, 2020 Commercial $ 2,247,059 $ 55,960 $ 38,186 $ 97,403 $ 10,091 $ 2,448,699 Mortgage warehouse 1,453,797 — — — — 1,453,797 Commercial real estate 5,379,801 306,884 317,580 92,411 — 6,096,676 Construction, land and land development 1,125,132 46,026 43,383 31,260 — 1,245,801 Residential real estate 1,332,757 6,296 5,726 7,686 — 1,352,465 Single-family interim construction 323,800 2,775 — — — 326,575 Agricultural 76,951 6,194 1,205 664 — 85,014 Consumer 66,970 8 — 90 — 67,068 $ 12,006,267 $ 424,143 $ 406,080 $ 229,514 $ 10,091 $ 13,076,095

Premises and Equipment, Net (Ta

Premises and Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Components of Premises and Equipment, Net	Premises and equipment, net at December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Land $ 78,900 $ 65,103 Building 193,475 191,940 Furniture, fixtures and equipment 47,576 39,282 Aircraft 8,947 8,947 Leasehold and tenant improvements 5,834 5,798 Construction in progress 45,263 915 379,995 311,985 Less accumulated depreciation (71,972) (62,518) $ 308,023 $ 249,467

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of Other Intangible Assets Activity	The following is a summary of other intangible assets activity: December 31, 2021 2020 Core deposit intangible: Balance at end of the year $ 125,884 $ 125,884 Less accumulated amortization (55,323) (43,235) Total core deposit intangible, net $ 70,561 $ 82,649 Customer relationship intangible: Balance at end of the year $ 6,407 $ 6,407 Less accumulated amortization (1,478) (986) Total customer relationship intangible, net $ 4,929 $ 5,421 Total other intangible assets, net $ 75,490 $ 88,070
Future Amortization Expense Related to Other Intangible Assets	The future amortization expense related to other intangible assets remaining at December 31, 2021 is as follows: First year $ 12,491 Second year 12,439 Third year 11,752 Fourth year 11,238 Fifth year 10,801 Thereafter 16,769 $ 75,490

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2021
Deposits [Abstract]
Components of Deposits	Deposits at December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Amount Percent Amount Percent Noninterest-bearing demand accounts $ 5,066,588 32.6 % $ 4,164,800 28.9 % Interest-bearing checking accounts 6,234,344 40.1 5,420,548 37.6 Savings accounts 758,727 4.9 654,733 4.6 Money market accounts 2,431,965 15.6 2,743,208 19.1 Certificates of deposit and individual retirement accounts (IRA), less than $250,000 540,011 3.5 675,329 4.7 Certificates of deposit and individual retirement accounts (IRA), $250,000 and greater 522,273 3.3 740,309 5.1 $ 15,553,908 100.0 % $ 14,398,927 100.0 %
Maturities of Certificates of Deposit	At December 31, 2021, the scheduled maturities of certificates of deposit, including IRAs, were as follows: First year $ 928,258 Second year 101,081 Third year 12,432 Fourth year 10,709 Fifth year 9,804 $ 1,062,284

Other Borrowings (Tables)

Other Borrowings (Tables)	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Other borrowings	Other borrowings at December 31, 2021 and 2020 consisted of the following: December 31, 2021 2020 Unsecured fixed rate subordinated debentures in the amount of $110,000. The balance of borrowings at December 31, 2021 and 2020 is net of discount and origination costs of $913 and $1,271, respectively. Interest payments of 5.875% are made semiannually on February 1 and August 1. The maturity date is August 1, 2024. The notes may not be redeemed prior to maturity and meet the criteria to be recognized as Tier 2 capital for regulatory purposes. (1)(2) $ 109,087 $ 108,729 Unsecured fixed-to-floating subordinated debentures in the original amount of $40,000. Interest payments initially of 5.75% are made semiannually on January 20 and July 20 through July 20, 2021. Thereafter, floating rate payments of 3 month LIBOR plus 4.73% are made quarterly in arrears beginning on October 20, 2021. The maturity date is July 20, 2026 with an optional redemption at July 20, 2021. (3) — 40,000 Unsecured fixed-to-floating subordinated debentures in the amount of $30,000. The balance of borrowings at December 31, 2021 and 2020 is net of origination costs of $465 and $543, respectively. Interest payments initially of 5.00% fixed rate are made semiannually on June 30 and December 31 through December 31, 2022. Thereafter, floating rate payments of 3 month LIBOR plus 2.83% are made quarterly in arrears beginning on March 31, 2023. The maturity date is December 31, 2027 with an optional redemption at December 31, 2022. The notes meet the criteria to be recognized as Tier 2 capital for regulatory purposes. (2) 29,535 29,457 Unsecured fixed-to-floating subordinated debentures in the amount of $130,000. The balance of borrowings at December 31, 2021 and 2020 is net of origination costs of $2,251 and $2,511, respectively. Interest payments initially of 4.00% fixed rate are made semiannually on March 15 and September 15 through September 15, 2025. Thereafter, floating rate payments equal to a benchmark rate (which is expected to be 3 month Secured Overnight Financing Rate (SOFR)) plus 3.885% payable quarterly in arrears beginning on December 15, 2025. The maturity date is September 15, 2030 with an optional redemption at September 15, 2025. The notes meet the criteria to be recognized as Tier 2 capital for regulatory purposes. (2) 127,749 127,489 Unsecured revolving line of credit with an unrelated commercial bank in the amount of $100,000. The line bears interest at LIBOR plus 1.75% and matured January 17, 2022. The Company is required to meet certain financial covenants on a quarterly basis, which includes certain restrictions on cash at IBG and meeting minimum capital ratios. (4) 17,000 6,500 $ 283,371 $ 312,175 ____________ (1) At December 31, 2021 and 2020, other borrowings included amounts owed to related parties of $50. (2) The permissible portion of qualified subordinated notes decreases 20% per year during the final five years of the term of the notes. (3) On July 20, 2021, the Company redeemed $40,000 of its outstanding 5.75% fixed-to-floating rate subordinated debentures. (4) Subsequent to December 31, 2021, the Company renewed the line (see Note 22. Subsequent Events ).

Junior Subordinated Debentures

Junior Subordinated Debentures (Tables)	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Schedule of Subordinated Borrowing	Information regarding the Debentures as of December 31, 2021 are summarized in the table below: Trust Preferred Securities Issued Debentures Carrying Value Repricing Frequency Interest Rate Interest Rate Index Maturity Date IB Trust I $ 5,155 $ 5,155 Quarterly 3.38% LIBOR + 3.25% March 2033 Guaranty Trust III 10,310 10,310 Quarterly 3.22 LIBOR + 3.10 July 2033 IB Trust II 3,093 3,093 Quarterly 2.97 LIBOR + 2.85 March 2034 Cenbank Trust III 15,464 15,464 Quarterly 2.77 LIBOR + 2.65 April 2034 IB Trust III 3,712 3,712 Quarterly 2.56 LIBOR +2.40 December 2035 IB Centex Trust I 2,578 2,578 Quarterly 3.41 LIBOR + 3.25 February 2035 Community Group Statutory Trust I 3,609 3,609 Quarterly 1.80 LIBOR + 1.60 June 2037 Northstar Trust II (1) 5,155 3,969 Quarterly 1.87 LIBOR + 1.67 June 2037 Northstar Trust III (1) 8,248 6,331 Quarterly 1.87 LIBOR + 1.67 September 2037 $ 57,324 $ 54,221 ____________

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Schedule of Net Lease Cost and Other Information Related to Operating Leases	The table below summarizes net lease cost: Years Ended December 31, 2021 2020 2019 Operating lease cost $ 6,567 $ 6,937 $ 7,025 Short term lease cost 64 124 103 Variable lease cost 1,645 1,631 1,829 Sublease income (282) (221) (228) Net lease cost $ 7,994 $ 8,471 $ 8,729 The table below summarizes other information related to operating leases: Years Ended December 31, 2021 2020 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 5,740 $ 6,091 Weighted average remaining lease term - operating leases, in years 7.41 7.23 Weighted average discount rate - operating leases 3.01 % 3.47 %
Summary of Lease Payment Obligations	The following table outlines lease payment obligations as outlined in the Company’s lease agreements for each of the next five years and thereafter in addition to a reconcilement to the Company’s current lease liability as of December 31, 2021. 2022 $ 5,308 2023 4,704 2024 4,109 2025 3,328 2026 1,882 Thereafter 6,921 Total lease payments 26,252 Less imputed interest (2,679) $ 23,573

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Income Tax Expense	Income tax expense for the years ended December 31, 2021, 2020 and 2019 was as follows: Years Ended December 31, 2021 2020 2019 Current income tax expense $ 52,130 $ 52,806 $ 39,426 Deferred income tax expense (benefit) 5,353 (1,633) 14,102 Income tax expense, as reported $ 57,483 $ 51,173 $ 53,528
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation between reported income tax expense and the amounts computed by applying the U.S. federal statutory income tax rate of 21% for the years ended December 31, 2021, 2020 and 2019 to income before income taxes is presented below: Years Ended December 31, 2021 2020 2019 Income tax expense computed at the statutory rate $ 59,269 $ 53,000 $ 51,715 Tax-exempt interest income from municipal securities (1,752) (1,779) (1,781) Tax-exempt loan income (1,359) (1,245) (1,174) Bank owned life insurance income (1,094) (1,123) (1,288) Non-deductible acquisition expenses — — 281 State taxes, net of federal benefit 2,516 2,660 3,455 Non-deductible compensation 473 — 2,017 Net tax expense (benefit) from stock based compensation (691) 243 21 Other 121 (583) 282 $ 57,483 $ 51,173 $ 53,528
Schedule of Deferred Tax Assets and Liabilities	Components of deferred tax assets and liabilities are presented in the table below. Deferred taxes as of December 31, 2021 and 2020 are based on the U.S. statutory federal income tax rate of 21%. December 31, 2021 2020 Deferred tax assets: Allowance for loan losses $ 33,463 $ 19,238 Lease liabilities under operating leases 5,141 5,129 NOL and tax credit carryforwards from acquisitions 3,354 3,718 Net unrealized loss on cash flow hedge 221 — Acquired loan fair market value adjustments 5,750 12,986 Stock-based compensation 1,822 1,567 Reserve for bonuses and other accrued expenses 3,775 3,409 Deferred loan fees and costs, net 2,800 — Acquired securities 1,611 2,095 Acquired intangibles 1,213 1,369 Start up costs 117 171 Unearned income 503 715 Deferred compensation 628 857 Noncompete agreements 540 597 Nonaccrual loans 463 550 Other 546 727 61,947 53,128 Deferred tax liabilities: Premises and equipment (10,376) (12,392) Right-of-use assets under operating leases (4,934) (4,911) Net unrealized gain on available for sale securities (1,457) (9,501) Intangible assets (16,464) (19,293) Acquired junior subordinated debentures fair value adjustment (677) (723) PPP deferred loan costs (192) (952) FHLB and other restricted stocks (335) (308) Acquired tax goodwill (735) (572) Other (599) (543) (35,769) (49,195) Net deferred tax asset $ 26,178 $ 3,933

Off-Balance Sheet Arrangement_2

Off-Balance Sheet Arrangements, Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	At December 31, 2021 and 2020, the approximate amounts of these financial instruments were as follows: December 31, 2021 2020 Commitments to extend credit $ 2,770,036 $ 2,268,216 Standby letters of credit 30,007 25,917 $ 2,800,043 $ 2,294,133
Commitments Off Balance Sheet Allowance for Credit Losses	The allowance for credit losses on off-balance sheet commitments was as follows: December 31, 2021 2020 2019 Balance at beginning of period $ — $ — $ — Impact of CECL adoption 1,113 — — Provision for off-balance sheet credit exposure 3,609 — — Balance at end of period $ 4,722 $ — $ —

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2021
Related Party Transactions [Abstract]
Loan Activity for Officers, Directors and Affiliates	Loan activity for officers, directors and their affiliates for the year ended December 31, 2021 is as follows: Balance at beginning of year $ 32,471 New loan originations 30,977 Repayments (21,596) Changes in affiliated persons (7,225) Balance at end of year $ 34,627

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Assets and Liabilities at Fair Value on Recurring Basis	The following table represents assets and liabilities reported on the consolidated balance sheets at their fair value on a recurring basis as of December 31, 2021 and 2020 by level within the ASC Topic 820 fair value measurement hierarchy: Fair Value Measurements at Reporting Date Using Assets/ Quoted Prices Significant Significant December 31, 2021 Assets: Investment securities available for sale: U.S. treasuries $ 174,996 $ — $ 174,996 $ — Government agency securities 444,675 — 444,675 — Obligations of state and municipal subdivisions 432,760 — 432,760 — Corporate bonds 34,796 — 34,796 — Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 918,550 — 918,550 — Other securities 950 — 950 — Loans held for sale, fair value option elected (1) 28,249 — 28,249 — Derivative financial instruments: Interest rate lock commitments 1,029 — 1,029 — Forward mortgage-backed securities trades 27 — 27 — Loan customer counterparty 6,459 — 6,459 — Financial institution counterparty 1,078 — 1,078 — Liabilities: Derivative financial instruments: Interest rate swaps - cash flow hedge 1,158 — 1,158 — Interest rate lock commitments 4 — 4 — Forward mortgage-backed securities trades 21 — 21 — Loan customer counterparty 1,073 — 1,073 — Financial institution counterparty 6,772 — 6,772 — December 31, 2020 Assets: Investment securities available for sale: U.S. treasuries $ 44,708 $ — $ 44,708 $ — Government agency securities 249,017 — 249,017 — Obligations of state and municipal subdivisions 393,165 — 393,165 — Corporate bonds 22,102 — 22,102 — Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA 443,501 — 443,501 — Other securities 1,200 — 1,200 — Loans held for sale, fair value option elected (1) 71,769 — 71,769 — Derivative financial instruments: Interest rate lock commitments 3,515 — 3,515 — Loan customer counterparty 20,159 — 20,159 — Liabilities: Derivative financial instruments: Forward mortgage-backed securities trades 568 — 568 — Financial institution counterparty 21,306 — 21,306 — ____________ (1) At December 31, 2021 and 2020, loans held for sale for which the fair value option was elected had an aggregate outstanding principal balance of $27,176 and $68,670, respectively. There were no mortgage loans held for sale under the fair value option that were 90 days or greater past due or on nonaccrual at December 31, 2021.
Assets and Liabilities at Fair Value on Nonrecurring Basis	The following table presents the assets carried on the consolidated balance sheet by caption and by level in the fair value hierarchy at December 31, 2021 and 2020, for which a nonrecurring change in fair value has been recorded: Fair Value Measurements at Reporting Date Using Assets Quoted Prices Significant Significant Period Ended December 31, 2021 Assets: Individually evaluated loans $ 11,204 $ — $ — $ 11,204 $ 3,526 December 31, 2020 Assets: Individually evaluated loans $ 16,903 $ — $ — $ 16,903 $ 13,041
Carrying Amount and Estimated Fair Value of Financial Instruments	The carrying amount, estimated fair value and the level of the fair value hierarchy of the Company’s financial instruments that are reported at amortized cost on the Company's consolidated balance sheets were as follows at December 31, 2021 and 2020: Fair Value Measurements at Reporting Date Using Carrying Estimated Quoted Prices Significant Significant December 31, 2021 Financial assets: Cash and cash equivalents $ 2,608,444 $ 2,608,444 $ 2,608,444 $ — $ — Certificates of deposit held in other banks 3,245 3,246 — 3,246 — Loans held for sale, at cost 3,875 3,982 — 3,982 — Loans, net 12,290,740 12,415,366 — — 12,415,366 FHLB of Dallas stock and other restricted stock 21,573 21,573 — 21,573 — Accrued interest receivable 49,636 49,636 — 49,636 — Financial liabilities: Deposits 15,553,908 15,553,645 — 15,553,645 — Accrued interest payable 5,301 5,301 — 5,301 — FHLB advances 150,000 128,555 — 128,555 — Other borrowings 283,371 303,250 — 303,250 — Junior subordinated debentures 54,221 45,501 — 45,501 — Off-balance sheet assets (liabilities): Commitments to extend credit — — — — — Standby letters of credit — — — — — December 31, 2020 Financial assets: Cash and cash equivalents $ 1,813,987 $ 1,813,987 $ 1,813,987 $ — $ — Certificates of deposit held in other banks 4,482 4,595 — 4,595 — Loans held for sale, at cost 10,878 11,138 — 11,138 — Loans, net 12,978,238 13,093,698 — — 13,093,698 FHLB of Dallas stock and other restricted stock 20,305 20,305 — 20,305 — Accrued interest receivable 60,581 60,581 — 60,581 — Financial liabilities: Deposits 14,398,927 14,407,596 — 14,407,596 — Accrued interest payable 7,397 7,397 — 7,397 — FHLB advances 375,000 371,175 — 371,175 — Other borrowings 312,175 327,150 — 327,150 — Junior subordinated debentures 54,023 42,624 — 42,624 — Off-balance sheet assets (liabilities): Commitments to extend credit — — — — — Standby letters of credit — — — — —

Derivative Financial Instrume_2

Derivative Financial Instruments - (Tables)	12 Months Ended
	Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Notional Balances and Fair Values of Outstanding Positions	The following table provides the outstanding notional balances and fair values of outstanding derivative positions at December 31, 2021 and 2020: Outstanding Notional Balance Asset Derivative Liability Derivative December 31, 2021 Derivatives designated as hedging instruments: Interest rate swaps - cash flow hedge $ 100,000 $ — $ 1,158 Derivatives not designated as hedging instruments: Interest rate lock commitments 34,064 1,029 4 Forward mortgage-backed securities trades 30,500 27 21 Commercial loan interest rate swaps: Loan customer counterparty 254,935 6,459 1,073 Financial institution counterparty 254,935 1,078 6,772 December 31, 2020 Derivatives not designated as hedging instruments: Interest rate lock commitments $ 116,795 $ 3,515 $ — Forward mortgage-backed securities trades 104,000 — 568 Commercial loan interest rate swaps: Loan customer counterparty 335,370 20,159 — Financial institution counterparty 335,370 — 21,306
Schedule of Weighted Average Interest Rate Received and Paid	The commercial loan customer counterparty weighted average received and paid interest rates for interest rate swaps outstanding were as follows: Weighted Average Interest Rate December 31, 2021 December 31, 2020 Received Paid Received Paid Loan customer counterparty 4.12 % 2.40 % 4.08 % 2.32 %
Income (Loss) on Derivatives Not Designated as Hedging Instruments	A summary of derivative activity and the related impact on the consolidated statements of income for the years ended December 31, 2021, 2020 and 2019 was as follows: Income Statement Location Years Ended December 31, 2021 2020 2019 Derivatives designated as hedging instruments Interest rate swaps - cash flow hedges Interest and fees on loans $ 584 $ — $ — Derivatives not designated as hedging instruments Interest rate lock commitments Mortgage banking revenue (2,490) 2,668 25 Forward mortgage-backed securities trades Mortgage banking revenue 574 (505) 163

Stock Awards (Tables)

Stock Awards (Tables)	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Nonvested Shares Activity	The following table summarizes the activity in nonvested restricted stock awards for the years ended December 31, 2021 and 2020: Restricted Stock Awards Number of Weighted Average Nonvested shares, December 31, 2020 468,800 $ 49.01 Granted during the period 115,463 66.10 Vested during the period (185,447) 51.18 Forfeited during the period (35,265) 50.23 Nonvested shares, December 31, 2021 363,551 $ 53.14 Nonvested shares, December 31, 2019 284,861 $ 58.63 Granted during the period 310,290 43.54 Vested during the period (115,436) 58.08 Forfeited during the period (10,915) 48.37 Nonvested shares, December 31, 2020 468,800 $ 49.01
Future Vesting Schedule of Nonvested Shares Activity	At December 31, 2021, the future vesting schedule of the nonvested restricted stock awards is as follows: Number of Shares First year 158,463 Second year 118,975 Third year 77,350 Fourth year 8,763 Total nonvested shares 363,551
Nonvested performance stock units	The following table summarizes the activity in nonvested performance stock units at target award level for the years ended December 31, 2021 and 2020: Performance-based Restricted Stock Units Number of Weighted Average Nonvested shares, December 31, 2020 89,300 $ 38.29 Granted during the period 25,198 63.92 Nonvested shares, December 31, 2021 114,498 $ 43.93 Nonvested shares, December 31, 2019 — $ — Granted during the period 89,300 38.29 Nonvested shares, December 31, 2020 89,300 $ 38.29

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2021
Regulated Operations [Abstract]
Schedule of Compliance with Regulatory Capital Requirements	The following table presents actual capital amounts and required ratios under Basel III Capital Rules for the Company and Bank as of December 31, 2021 and December 31, 2020. Actual Minimum Capital To Be Well Amount Ratio Amount Ratio Amount Ratio December 31, 2021 Total capital to risk weighted assets: Consolidated $ 1,916,163 13.67 % $ 1,471,510 10.50 % N/A N/A Bank 1,983,530 14.16 1,471,036 10.50 $ 1,400,987 10.00 % Tier 1 capital to risk weighted assets: Consolidated 1,614,372 11.52 1,191,223 8.50 N/A N/A Bank 1,885,739 13.46 1,190,839 8.50 1,120,790 8.00 Common equity tier 1 to risk weighted assets: Consolidated 1,558,772 11.12 981,007 7.00 N/A N/A Bank 1,885,739 13.46 980,691 7.00 910,642 6.50 Tier 1 capital to average assets: Consolidated 1,614,372 8.80 733,954 4.00 N/A N/A Bank 1,885,739 10.28 733,785 4.00 917,231 5.00 December 31, 2020 Total capital to risk weighted assets: Consolidated $ 1,825,661 13.32 % $ 1,438,939 10.50 % N/A N/A Bank 1,864,240 13.61 1,438,385 10.50 $ 1,369,891 10.00 % Tier 1 capital to risk weighted assets: Consolidated 1,471,841 10.74 1,164,855 8.50 N/A N/A Bank 1,776,420 12.97 1,164,407 8.50 1,095,913 8.00 Common equity tier 1 to risk weighted assets: Consolidated 1,416,241 10.33 959,293 7.00 N/A N/A Bank 1,776,420 12.97 958,924 7.00 890,429 6.50 Tier 1 capital to average assets: Consolidated 1,471,841 9.12 645,730 4.00 N/A N/A Bank 1,776,420 11.01 645,539 4.00 806,924 5.00

Parent Company Only Financial_2

Parent Company Only Financial Statements (Tables)	12 Months Ended
	Dec. 31, 2021
Condensed Financial Information Disclosure [Abstract]
Balance Sheet for the Parent Company	The following balance sheets, statements of income and statements of cash flows for Independent Bank Group, Inc. should be read in conjunction with the consolidated financial statements and the notes thereto. Balance Sheets December 31, Assets 2021 2020 Cash and cash equivalents $ 10,747 $ 5,482 Investment in subsidiaries 2,904,395 2,876,171 Investment in trusts 1,724 1,724 Other assets 3,039 3,849 Total assets $ 2,919,905 $ 2,887,226 Liabilities and Stockholders' Equity Other borrowings $ 283,371 $ 312,175 Junior subordinated debentures 54,221 54,023 Other liabilities 5,663 5,657 Total liabilities 343,255 371,855 Stockholders' equity: Preferred stock — — Common stock 428 431 Additional paid-in capital 1,945,497 1,934,807 Retained earnings 625,484 543,800 Accumulated other comprehensive income 5,241 36,333 Total stockholders' equity 2,576,650 2,515,371 Total liabilities and stockholders' equity $ 2,919,905 $ 2,887,226
Statement of Income for the Parent Company	Statements of Income Years Ended December 31, 2021 2020 2019 Interest expense: Interest on other borrowings $ 15,247 $ 12,446 $ 11,561 Interest on junior subordinated debentures 1,756 2,162 3,028 Total interest expense 17,003 14,608 14,589 Noninterest income: Dividends from subsidiaries 134,547 83,314 105,877 Other 61 — 1 Total noninterest income 134,608 83,314 105,878 Noninterest expense: Salaries and employee benefits 10,546 8,346 7,653 Professional fees 126 202 264 Acquisition expense, including legal — 16,225 33,445 Other 2,510 2,424 2,562 Total noninterest expense 13,182 27,197 43,924 Income before income tax benefit and equity in undistributed income of subsidiaries 104,423 41,509 47,365 Income tax benefit 7,131 9,410 11,066 Income before equity in undistributed income of subsidiaries 111,554 50,919 58,431 Equity in undistributed income of subsidiaries 113,196 150,290 134,305 Net income $ 224,750 $ 201,209 $ 192,736
Statement of Cash Flows for the Parent Company	Statements of Cash Flows Years Ended December 31, 2021 2020 2019 Cash flows from operating activities: Net income $ 224,750 $ 201,209 $ 192,736 Adjustments to reconcile net income to net cash provided by operating activities: Equity in undistributed net income of subsidiaries (113,196) (150,290) (134,305) Amortization of discount and origination costs on borrowings 894 720 633 Stock based compensation expense 10,691 8,450 7,808 Excess tax (benefit) expense on restricted stock vested (691) 243 21 Deferred tax (benefit) expense (210) 96 2,165 Net change in other assets 1,020 (590) 1,863 Net change in other liabilities 500 (952) (64) Net cash provided by operating activities 123,758 58,886 70,857 Cash flows from investing activities: Capital investment in subsidiaries — (120,000) — Cash acquired in connection with acquisition — — 339 Cash paid in connection with acquisition — — (9) Net cash (used in) provided by investing activities — (120,000) 330 Cash flows from financing activities: Proceeds from other borrowings 75,000 148,653 65,000 Repayments of other borrowings (104,500) (39,250) (40,500) Offering costs paid in connection with acquired bank — — (804) Repurchase of common stock (32,132) (5,819) (51,659) Dividends paid (56,861) (45,265) (43,302) Net cash (used in) provided by financing activities (118,493) 58,319 (71,265) Net change in cash and cash equivalents 5,265 (2,795) (78) Cash and cash equivalents at beginning of year 5,482 8,277 8,355 Cash and cash equivalents at end of year $ 10,747 $ 5,482 $ 8,277

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021business_trustsegment
Summary Of Significant Accounting Policies [Line Items]
Number of wholly owned statutory business trusts | business_trust	9
Number of reportable segments | segment	1
Core deposit intangibles
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible assets, useful life	10 years
Customer relationship intangibles
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible assets, useful life	13 years
Minimum
Summary Of Significant Accounting Policies [Line Items]
Premises and equipment, useful life	3 years
Minimum | Computer Software, Intangible Asset
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible assets, useful life	1 year
Maximum
Summary Of Significant Accounting Policies [Line Items]
Premises and equipment, useful life	30 years
Maximum | Computer Software, Intangible Asset
Summary Of Significant Accounting Policies [Line Items]
Finite-lived intangible assets, useful life	5 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - EPS (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Basic earnings per share:
Net income	$ 224,750	$ 201,209	$ 192,736
Undistributed earnings allocated to participating securities	1,576	1,311	971
Dividends paid on participating securities	534	380	281
Net income available to common shareholders	$ 222,640	$ 199,518	$ 191,484
Weighted-average basic shares outstanding (shares)	42,666,007	42,754,606	42,964,393
Basic earnings per share (usd per share)	$ 5.22	$ 4.67	$ 4.46
Diluted earnings per share:
Total weighted-average diluted shares outstanding (shares)	42,724,792	42,754,606	42,964,393
Diluted earnings per share (usd per share)	$ 5.21	$ 4.67	$ 4.46
Anti-dilutive participating securities (shares)	181,016	58,359	73,546
Performance stock units
Diluted earnings per share:
Add dilutive (shares)	58,785	0	0

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Jan. 01, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect reduction to retained earnings	$ (2,576,650)		$ (2,515,371)	$ (2,339,773)		$ (1,606,433)
Deferred tax asset	33,463	$ 15,113	19,238
Financing Receivable, Allowance for Credit Loss		87,820
Right-of-use assets	24,126		24,841
Lease liability	23,573		23,413
Retained earnings	(625,484)		(543,800)
Receivables Acquired with Deteriorated Credit Quality | Accounting Standards Update 2016-13
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		13,035
Cumulative effect of change in accounting principle
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect reduction to retained earnings			53,880			926
Financing Receivable, Allowance for Credit Loss		67,880
Right-of-use assets					$ 38,812
Lease liability					33,953
Prepaid rent					4,949
Retained earnings					$ 70
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		$ 13,035
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect reduction to retained earnings	$ (625,484)		(543,800)	$ (393,674)		(296,816)
Retained Earnings | Cumulative effect of change in accounting principle
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect reduction to retained earnings			$ 53,880			$ 926

Recent Accounting Pronounceme_3

Recent Accounting Pronouncements - CECL (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Jan. 01, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		$ 87,820
Allowance for credit losses on off-balance-sheet credit exposures	$ 4,722	0	$ 0	$ 0	$ 0
Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		27,311
Real estate | Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		36,698
Real estate | Commercial construction, land and land development
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		13,425
Real estate | Residential Real Estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		6,786
Real estate | Single-family interim construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		2,156
Agricultural
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		337
Consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		684
Unallocated
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		423
Cumulative effect of change in accounting principle
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		67,880
Allowance for credit losses on off-balance-sheet credit exposures		1,113	$ 1,113	$ 0	$ 0
Cumulative effect of change in accounting principle | Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		12,775
Cumulative effect of change in accounting principle | Real estate | Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		29,108
Cumulative effect of change in accounting principle | Real estate | Commercial construction, land and land development
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		22,008
Cumulative effect of change in accounting principle | Real estate | Residential Real Estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		(2,255)
Cumulative effect of change in accounting principle | Real estate | Single-family interim construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		7,179
Cumulative effect of change in accounting principle | Agricultural
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		(178)
Cumulative effect of change in accounting principle | Consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		(334)
Cumulative effect of change in accounting principle | Unallocated
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		(423)
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		13,035
Allowance for credit losses on off-balance-sheet credit exposures		0
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality | Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		4,328
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality | Real estate | Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		7,640
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality | Real estate | Commercial construction, land and land development
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		927
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality | Real estate | Residential Real Estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		140
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality | Real estate | Single-family interim construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		0
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality | Agricultural
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		0
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality | Consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		0
Cumulative effect of change in accounting principle | Receivables Acquired with Deteriorated Credit Quality | Unallocated
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		0
Cumulative effect, period of adoption, adjusted balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		168,735
Allowance for credit losses on off-balance-sheet credit exposures		1,113
Cumulative effect, period of adoption, adjusted balance | Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		44,414
Cumulative effect, period of adoption, adjusted balance | Real estate | Commercial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		73,446
Cumulative effect, period of adoption, adjusted balance | Real estate | Commercial construction, land and land development
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		36,360
Cumulative effect, period of adoption, adjusted balance | Real estate | Residential Real Estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		4,671
Cumulative effect, period of adoption, adjusted balance | Real estate | Single-family interim construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		9,335
Cumulative effect, period of adoption, adjusted balance | Agricultural
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		159
Cumulative effect, period of adoption, adjusted balance | Consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		350
Cumulative effect, period of adoption, adjusted balance | Unallocated
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Financing Receivable, Allowance for Credit Loss		$ 0

Statement of Cash Flows - Other

Statement of Cash Flows - Other Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash transactions:
Interest expense paid	$ 65,336	$ 97,246	$ 144,775
Income taxes paid	58,083	54,842	40,504
Noncash transactions:
Deferred dividend equivalents	197	0	0
Transfers of loans to other real estate owned	0	5,239	544
Loans to facilitate the sale of other real estate owned	0	2,039	517
Securities purchased, not yet settled	0	0	9,975
Transfers of loans held for investment to loans held for sale	0	0	83,526
Right-of-use assets obtained in exchange for lease liabilities	5,156	105	35,553
Loans purchased, not yet settled	29,332	9,442	0
Transfer of bank premises to other real estate	0	0	7,896
Transfer of repurchase agreements to deposits	$ 0	$ 0	$ 8,475

Statement of Cash Flows - Nonca

Statement of Cash Flows - Noncash Investing from Branch Sale (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Noncash liabilities transferred:
Deposit premium received	$ 1,386
Cash paid to buyer, net of deposit premium	24,957
Sale of Branch
Noncash assets transferred:
Loans, including accrued interest	796
Premises and equipment	94
Other assets	2
Total assets	892
Noncash liabilities transferred:
Deposits, including interest	27,721
Other liabilities	27
Total liabilities	27,748
Sale of Branch | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Noncash liabilities transferred:
Cash and cash equivalents transferred in branch sales	$ 206

Statement of Cash Flows - Non_2

Statement of Cash Flows - Noncash Investing from Sale of Trust Business (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Noncash assets transferred:
Net cash received from sale	$ 0	$ 0	$ 4,269
Trust Business Sale
Noncash assets transferred:
Customer relationship intangible assets, net			2,939
Other assets			11
Total assets			2,950
Trust Business Sale | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Noncash assets transferred:
Net cash received from sale			$ 4,269

Statement of Cash Flows - Non_3

Statement of Cash Flows - Noncash Investing Activities from Acquisitions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Noncash assets acquired
Certificates of deposit held in other banks			$ 262
Securities available for sale			561,052
Restricted stock			27,794
Loans			2,789,868
Premises and equipment			65,786
Other real estate owned			1,829
Goodwill			272,224
Other intangible assets			71,518
Bank owned life insurance			80,837
Other assets			31,987
Total assets acquired			3,903,157
Noncash liabilities assumed:
Deposits			3,108,810
Repurchase agreements			8,475
FHLB advances			142,653
Other borrowings			40,000
Junior subordinated debentures			25,774
Other liabilities			15,477
Total liabilities assumed			3,341,189
Cash and cash equivalents acquired from acquisitions	$ 0	$ 0	39,913
Cash paid to shareholders of acquired banks	$ 0	$ 0	9
Fair value of common stock issued to shareholders of acquired banks			$ 601,872

Securities Available for Sale -

Securities Available for Sale - Amortized Cost of Securities and Approximate Fair Values (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost (1)	$ 1,999,792	$ 1,108,453
Gross Unrealized Gains	29,004	47,271
Gross Unrealized Losses	(22,069)	(2,031)
Fair Value	2,006,727	1,153,693
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss	8,581	6,242
U.S. treasuries
Debt Securities, Available-for-sale [Line Items]
Amortized Cost (1)	174,950	43,060
Gross Unrealized Gains	724	1,648
Gross Unrealized Losses	(678)	0
Fair Value	174,996	44,708
Government agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost (1)	453,402	247,764
Gross Unrealized Gains	1,221	3,169
Gross Unrealized Losses	(9,948)	(1,916)
Fair Value	444,675	249,017
Obligations of state and municipal subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost (1)	418,554	373,017
Gross Unrealized Gains	15,440	20,168
Gross Unrealized Losses	(1,234)	(20)
Fair Value	432,760	393,165
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost (1)	33,994	21,496
Gross Unrealized Gains	862	608
Gross Unrealized Losses	(60)	(2)
Fair Value	34,796	22,102
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA
Debt Securities, Available-for-sale [Line Items]
Amortized Cost (1)	917,942	421,916
Gross Unrealized Gains	10,757	21,678
Gross Unrealized Losses	(10,149)	(93)
Fair Value	918,550	443,501
Other securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost (1)	950	1,200
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 950	$ 1,200

Securities Available for Sale_2

Securities Available for Sale - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Abstract]
Carrying value of securities pledged	$ 997,416	$ 738,519
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0

Securities Available for Sale_3

Securities Available for Sale - Proceeds from Sale, Gross Gains and Losses of Securities Available for Sale (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Abstract]
Proceeds from sale	$ 9,294	$ 13,862	$ 192,417
Gross gains	13	385	306
Gross losses	$ 0	$ 3	$ 31

Securities Available for Sale_4

Securities Available for Sale - Amortized Cost and Estimated Fair Value of Securities Available for Sale by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amortized Cost (1)
Due in one year or less	$ 31,164
Due from one year to five years	198,803
Due from five to ten years	460,251
Thereafter	391,632
Single maturity dates, amortized cost basis	1,081,850
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA	917,942
Amortized Cost (1)	1,999,792	$ 1,108,453
Fair Value
Due in one year or less	31,526
Due from one year to five years	202,479
Due from five to ten years	459,017
Thereafter	395,155
Single maturity dates, fair value	1,088,177
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA	918,550
Fair value, total	$ 2,006,727	$ 1,153,693

Securities Available for Sale_5

Securities Available for Sale - Summary of Unrealized Losses and Fair Value of Securities in Continuous Unrealized Loss Positions (Details) $ in Thousands	Dec. 31, 2021USD ($)security	Dec. 31, 2020USD ($)security
Debt Securities, Available-for-sale [Line Items]
Less than 12 months: number of securities | security	192	33
Less than 12 months: estimated fair value	$ 1,084,863	$ 159,025
Less than 12 months: unrealized losses	$ (14,819)	$ (2,031)
Greater than 12 months: number of securities | security	35	0
Greater than 12 months: estimated fair value	$ 168,138	$ 0
Greater than 12 months: unrealized losses	(7,250)	0
Total: estimated fair value	1,253,001	159,025
Total: unrealized losses	$ (22,069)	$ (2,031)
U.S. treasuries
Debt Securities, Available-for-sale [Line Items]
Less than 12 months: number of securities | security	22
Less than 12 months: estimated fair value	$ 144,172
Less than 12 months: unrealized losses	$ (678)
Greater than 12 months: number of securities | security	0
Greater than 12 months: estimated fair value	$ 0
Greater than 12 months: unrealized losses	0
Total: estimated fair value	144,172
Total: unrealized losses	$ (678)
Government agency securities
Debt Securities, Available-for-sale [Line Items]
Less than 12 months: number of securities | security	38	20
Less than 12 months: estimated fair value	$ 258,334	$ 112,897
Less than 12 months: unrealized losses	$ (4,622)	$ (1,916)
Greater than 12 months: number of securities | security	22	0
Greater than 12 months: estimated fair value	$ 119,963	$ 0
Greater than 12 months: unrealized losses	(5,326)	0
Total: estimated fair value	378,297	112,897
Total: unrealized losses	$ (9,948)	$ (1,916)
Obligations of state and municipal subdivisions
Debt Securities, Available-for-sale [Line Items]
Less than 12 months: number of securities | security	14	2
Less than 12 months: estimated fair value	$ 47,200	$ 3,786
Less than 12 months: unrealized losses	$ (988)	$ (20)
Greater than 12 months: number of securities | security	2	0
Greater than 12 months: estimated fair value	$ 3,555	$ 0
Greater than 12 months: unrealized losses	(246)	0
Total: estimated fair value	50,755	3,786
Total: unrealized losses	$ (1,234)	$ (20)
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Less than 12 months: number of securities | security	3	1
Less than 12 months: estimated fair value	$ 13,440	$ 998
Less than 12 months: unrealized losses	$ (60)	$ (2)
Greater than 12 months: number of securities | security	0	0
Greater than 12 months: estimated fair value	$ 0	$ 0
Greater than 12 months: unrealized losses	0	0
Total: estimated fair value	13,440	998
Total: unrealized losses	$ (60)	$ (2)
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA
Debt Securities, Available-for-sale [Line Items]
Less than 12 months: number of securities | security	115	10
Less than 12 months: estimated fair value	$ 621,717	$ 41,344
Less than 12 months: unrealized losses	$ (8,471)	$ (93)
Greater than 12 months: number of securities | security	11	0
Greater than 12 months: estimated fair value	$ 44,620	$ 0
Greater than 12 months: unrealized losses	(1,678)	0
Total: estimated fair value	666,337	41,344
Total: unrealized losses	$ (10,149)	$ (93)

Loans, Net and Allowance for _3

Loans, Net and Allowance for Credit Losses on Loans - Composition of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts Notes And Loans Receivable [Line Items]
Loans	$ 12,439,446
Loans, before deferred fees		$ 13,076,095
Deferred loan fees, net	(9,406)	(10,037)
Allowance for credit losses	(148,706)	(87,820)	$ (51,461)	$ (44,802)
Total loans, net	12,290,740	12,978,238
Accrued Interest Receivable	41,051	54,328
Commercial
Accounts Notes And Loans Receivable [Line Items]
Loans	1,983,886
Loans, before deferred fees		2,448,699
Allowance for credit losses	(49,747)	(27,311)	(12,844)	(11,793)
Mortgage warehouse
Accounts Notes And Loans Receivable [Line Items]
Loans	788,848
Loans, before deferred fees		1,453,797
Real estate | Commercial
Accounts Notes And Loans Receivable [Line Items]
Loans	6,617,455
Loans, before deferred fees		6,096,676
Allowance for credit losses	(65,110)	(36,698)	(24,371)	(21,343)
Real estate | Commercial construction, land and land development
Accounts Notes And Loans Receivable [Line Items]
Loans	1,180,181
Loans, before deferred fees		1,245,801
Allowance for credit losses	(23,861)	(13,425)	(8,714)	(6,452)
Real estate | Residential Real Estate
Accounts Notes And Loans Receivable [Line Items]
Loans	1,300,122
Loans, before deferred fees		1,352,465
Allowance for credit losses	(2,192)	(6,786)	(3,678)	(3,320)
Real estate | Single-family interim construction
Accounts Notes And Loans Receivable [Line Items]
Loans	380,627
Loans, before deferred fees		326,575
Allowance for credit losses	(7,222)	(2,156)	(1,606)	(1,402)
Agricultural
Accounts Notes And Loans Receivable [Line Items]
Loans	106,512
Loans, before deferred fees		85,014
Allowance for credit losses	(106)	(337)	(332)	(241)
Consumer
Accounts Notes And Loans Receivable [Line Items]
Loans	81,815
Loans, before deferred fees		67,068
Allowance for credit losses	$ (468)	$ (684)	$ (231)	$ (189)

Loans, Net and Allowance for _4

Loans, Net and Allowance for Credit Losses on Loans - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021USD ($)modified_loan	Dec. 31, 2020USD ($)modified_loan
Accounts Notes And Loans Receivable [Line Items]
Energy Related Commercial Loans	$ 12,290,740,000	$ 12,978,238,000
Troubled debt restructuring modification recorded investment	$ 2,918,000	$ 2,564,000
Number of loans modified under troubled debt restructuring | modified_loan	0	0
Commitments to lend additional funds	$ 0	$ 0
Loans and Leases, Net | COLORADO | Geographic Concentration Risk
Accounts Notes And Loans Receivable [Line Items]
Percentage of portfolio	24.00%
Owner Occupied | Loans and Leases, Net | Customer Concentration Risk
Accounts Notes And Loans Receivable [Line Items]
Percentage of portfolio	26.00%
Commercial | Paycheck Protection Program
Accounts Notes And Loans Receivable [Line Items]
PPP interest rate	1.00%
PPP loans outstanding	$ 112,128,000	804,397,000
PPP deferred loan fees	(2,552,000)
PPP deferred loan fees		9,770,000
Commercial | Shared National Credits (SNC)
Accounts Notes And Loans Receivable [Line Items]
Energy Related Commercial Loans	294,351,000	187,589,000
Commercial | Energy Related Loans
Accounts Notes And Loans Receivable [Line Items]
Energy Related Commercial Loans	$ 342,776,000	$ 205,496,000
Commercial | Mortgage warehouse
Accounts Notes And Loans Receivable [Line Items]
Duration of the loans to larger mortgage originators	60 days
Agricultural | Real Estate Loan
Accounts Notes And Loans Receivable [Line Items]
Loan to value ratio (percent)	80.00%
Loan, amortization period	20 years
Agricultural | Non-Real Estate Loan
Accounts Notes And Loans Receivable [Line Items]
Period of operating lines	1 year
Consumer | Loans and Leases, Net | Customer Concentration Risk
Accounts Notes And Loans Receivable [Line Items]
Percentage of portfolio	1.00%
Maximum | Commercial | Paycheck Protection Program
Accounts Notes And Loans Receivable [Line Items]
PPP term	5 years
Maximum | Commercial | Mortgage warehouse
Accounts Notes And Loans Receivable [Line Items]
Duration of the loans to mortgage bankers	15 days
Minimum
Accounts Notes And Loans Receivable [Line Items]
Loans requiring external review	$ 3,000,000
Minimum | Commercial | Paycheck Protection Program
Accounts Notes And Loans Receivable [Line Items]
PPP term	2 years

Loans, Net and Allowance for _5

Loans, Net and Allowance for Credit Losses on Loans - Rollforward of Activity in Credit Losses (Details) - USD ($) $ in Thousands	Jan. 01, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	$ 87,820	$ 87,820	$ 51,461	$ 44,802
Provision for credit losses		(12,609)	42,993	14,805
Charge-offs		(7,531)	(6,873)	(8,364)
Recoveries		111	239	218
Balance at end of period		148,706	87,820	51,461
Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	67,880
Initial allowance on loans purchased with credit deterioration	13,035
Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	27,311	27,311	12,844	11,793
Provision for credit losses		12,130	20,025	8,670
Charge-offs		(6,856)	(5,670)	(7,709)
Recoveries		59	112	90
Balance at end of period		49,747	27,311	12,844
Commercial | Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	12,775
Initial allowance on loans purchased with credit deterioration	4,328
Real estate | Commercial
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	36,698	36,698	24,371	21,343
Provision for credit losses		(7,961)	13,058	3,027
Charge-offs		(375)	(735)	(3)
Recoveries		0	4	4
Balance at end of period		65,110	36,698	24,371
Real estate | Commercial | Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	29,108
Initial allowance on loans purchased with credit deterioration	7,640
Real estate | Commercial construction, land and land development
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	13,425	13,425	8,714	6,452
Provision for credit losses		(12,373)	4,711	2,262
Charge-offs		(126)	0	0
Recoveries		0	0	0
Balance at end of period		23,861	13,425	8,714
Real estate | Commercial construction, land and land development | Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	22,008
Initial allowance on loans purchased with credit deterioration	927
Real estate | Residential Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	6,786	6,786	3,678	3,320
Provision for credit losses		(2,486)	3,108	498
Charge-offs		0	0	(140)
Recoveries		7	0	0
Balance at end of period		2,192	6,786	3,678
Real estate | Residential Real Estate | Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	(2,255)
Initial allowance on loans purchased with credit deterioration	140
Real estate | Single-family interim construction
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	2,156	2,156	1,606	1,402
Provision for credit losses		(2,113)	632	207
Charge-offs		0	(82)	(3)
Recoveries		0	0	0
Balance at end of period		7,222	2,156	1,606
Real estate | Single-family interim construction | Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	7,179
Initial allowance on loans purchased with credit deterioration	0
Agricultural
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	337	337	332	241
Provision for credit losses		(53)	5	91
Charge-offs		0	0	0
Recoveries		0	0	0
Balance at end of period		106	337	332
Agricultural | Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	(178)
Initial allowance on loans purchased with credit deterioration	0
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	684	684	231	189
Provision for credit losses		247	716	427
Charge-offs		(174)	(386)	(509)
Recoveries		45	123	124
Balance at end of period		468	684	231
Consumer | Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	(334)
Initial allowance on loans purchased with credit deterioration	0
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Balance at beginning of period	423	423	(315)	62
Provision for credit losses		0	738	(377)
Charge-offs		0	0	0
Recoveries		0	0	0
Balance at end of period		$ 0	$ 423	$ (315)
Unallocated | Cumulative effect of change in accounting principle
Allowance for Loan and Lease Losses [Roll Forward]
Impact of adopting ASC 326	(423)
Initial allowance on loans purchased with credit deterioration	$ 0

Loans, Net and Allowance for _6

Loans, Net and Allowance for Credit Losses on Loans - Individually Evaluated Loans by Loan Class (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Impaired [Line Items]
Loan Balance - Amortized Cost Basis	$ 64,944	$ 64,383
Specific Allocations	18,073	8,524
Commercial
Financing Receivable, Impaired [Line Items]
Loan Balance - Amortized Cost Basis	38,911	39,298
Specific Allocations	15,958	8,281
Real estate | Commercial
Financing Receivable, Impaired [Line Items]
Loan Balance - Amortized Cost Basis	24,683	21,848
Specific Allocations	1,553	243
Real estate | Commercial construction, land and land development
Financing Receivable, Impaired [Line Items]
Loan Balance - Amortized Cost Basis	1,350	32
Specific Allocations	562	0
Real estate | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Loan Balance - Amortized Cost Basis	0	2,550
Specific Allocations	0	0
Real estate | Single-family interim construction
Financing Receivable, Impaired [Line Items]
Loan Balance - Amortized Cost Basis	0	0
Specific Allocations	0	0
Agricultural
Financing Receivable, Impaired [Line Items]
Loan Balance - Amortized Cost Basis	0	613
Specific Allocations	0	0
Consumer
Financing Receivable, Impaired [Line Items]
Loan Balance - Amortized Cost Basis	0	42
Specific Allocations	$ 0	$ 0

Loans, Net and Allowance for _7

Loans, Net and Allowance for Credit Losses on Loans - Summary of Non Performing Loans by Loan Class (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)numberOfNonaccrualNoAllowance	Dec. 31, 2020USD ($)
Accounts Notes And Loans Receivable [Line Items]
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	$ 2,918	$ 2,564
Nonaccrual, No Allowance	18
Nonaccrual, Interest Income	$ 0
Commercial
Accounts Notes And Loans Receivable [Line Items]
Number of Nonaccrual, No Allowance | numberOfNonaccrualNoAllowance	1
Nonperforming Loans
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans (1)	$ 53,673	48,997
Loans past due 90 days and still accruing	1,790	433
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	1,875	1,986
Total nonperforming loans	57,338	51,416
Nonperforming Loans | Commercial
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans (1)	36,802	25,898
Loans past due 90 days and still accruing	187	433
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	0	0
Total nonperforming loans	36,989	26,331
Nonperforming Loans | Real estate | Commercial
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans (1)	15,218	20,040
Loans past due 90 days and still accruing	0	0
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	1,714	1,808
Total nonperforming loans	16,932	21,848
Nonperforming Loans | Real estate | Commercial construction, land and land development
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans (1)	23	32
Loans past due 90 days and still accruing	0	0
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	0	0
Total nonperforming loans	23	32
Nonperforming Loans | Real estate | Residential Real Estate
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans (1)	1,592	2,372
Loans past due 90 days and still accruing	1,603	0
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	161	178
Total nonperforming loans	3,356	2,550
Nonperforming Loans | Real estate | Single-family interim construction
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans (1)	0	0
Loans past due 90 days and still accruing	0	0
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	0	0
Total nonperforming loans	0	0
Nonperforming Loans | Agricultural
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans (1)	0	613
Loans past due 90 days and still accruing	0	0
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	0	0
Total nonperforming loans	0	613
Nonperforming Loans | Consumer
Accounts Notes And Loans Receivable [Line Items]
Nonaccrual loans (1)	38	42
Loans past due 90 days and still accruing	0	0
Troubled debt restructurings (not included in nonaccrual or loans past due and still accruing)	0	0
Total nonperforming loans	$ 38	$ 42

Loans, Net and Allowance for _8

Loans, Net and Allowance for Credit Losses on Loans - Summary of Troubled Debt Restructurings (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)contract	Dec. 31, 2020USD ($)contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts | contract	3	1
Pre-restructuring outstanding recorded investment	$ 1,795	$ 1,517
Post-restructuring outstanding recorded investment	$ 576	$ 1,517
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts | contract	2	0
Pre-restructuring outstanding recorded investment	$ 1,789	$ 0
Post-restructuring outstanding recorded investment	$ 570	$ 0
Real estate | Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts | contract	0	1
Pre-restructuring outstanding recorded investment	$ 0	$ 1,517
Post-restructuring outstanding recorded investment	$ 0	$ 1,517
Real estate | Commercial construction, land and land development
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts | contract	0	0
Pre-restructuring outstanding recorded investment	$ 0	$ 0
Post-restructuring outstanding recorded investment	$ 0	$ 0
Real estate | Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts | contract	0	0
Pre-restructuring outstanding recorded investment	$ 0	$ 0
Post-restructuring outstanding recorded investment	$ 0	$ 0
Real estate | Single-family interim construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts | contract	0	0
Pre-restructuring outstanding recorded investment	$ 0	$ 0
Post-restructuring outstanding recorded investment	$ 0	$ 0
Agricultural
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts | contract	0	0
Pre-restructuring outstanding recorded investment	$ 0	$ 0
Post-restructuring outstanding recorded investment	$ 0	$ 0
Consumer
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of contracts | contract	1	0
Pre-restructuring outstanding recorded investment	$ 6	$ 0
Post-restructuring outstanding recorded investment	$ 6	$ 0

Loans, Net and Allowance for _9

Loans, Net and Allowance for Credit Losses on Loans - Aging of Past Due Loans by Loan Class (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Loans	$ 12,439,446
Loans, before deferred fees		$ 13,076,095
Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		214,786
Commercial
Financing Receivable, Past Due [Line Items]
Loans	1,983,886
Loans, before deferred fees		2,448,699
Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans	788,848
Loans, before deferred fees		1,453,797
Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans	6,617,455
Loans, before deferred fees		6,096,676
Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans	1,180,181
Loans, before deferred fees		1,245,801
Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans	1,300,122
Loans, before deferred fees		1,352,465
Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans	380,627
Loans, before deferred fees		326,575
Agricultural
Financing Receivable, Past Due [Line Items]
Loans	106,512
Loans, before deferred fees		85,014
Consumer
Financing Receivable, Past Due [Line Items]
Loans	81,815
Loans, before deferred fees		67,068
Loans 30-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans	9,262
Loans, before deferred fees		11,575
Loans 30-89 Days Past Due | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		624
Loans 30-89 Days Past Due | Commercial
Financing Receivable, Past Due [Line Items]
Loans	1,041
Loans 30-89 Days Past Due | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans	0
Loans 30-89 Days Past Due | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans	2,861
Loans 30-89 Days Past Due | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans	0
Loans 30-89 Days Past Due | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans	3,838
Loans 30-89 Days Past Due | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans	1,290
Loans 30-89 Days Past Due | Agricultural
Financing Receivable, Past Due [Line Items]
Loans	16
Loans 30-89 Days Past Due | Consumer
Financing Receivable, Past Due [Line Items]
Loans	216
Loans 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans	24,762
Loans, before deferred fees		34,306
Loans 90 Days or More Past Due | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		3,219
Loans 90 Days or More Past Due | Commercial
Financing Receivable, Past Due [Line Items]
Loans	11,056
Loans 90 Days or More Past Due | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans	0
Loans 90 Days or More Past Due | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans	11,784
Loans 90 Days or More Past Due | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans	0
Loans 90 Days or More Past Due | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans	1,913
Loans 90 Days or More Past Due | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans	0
Loans 90 Days or More Past Due | Agricultural
Financing Receivable, Past Due [Line Items]
Loans	0
Loans 90 Days or More Past Due | Consumer
Financing Receivable, Past Due [Line Items]
Loans	9
Total Past Due Loans
Financing Receivable, Past Due [Line Items]
Loans	34,024
Loans, before deferred fees		45,881
Total Past Due Loans | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		3,843
Total Past Due Loans | Commercial
Financing Receivable, Past Due [Line Items]
Loans	12,097
Total Past Due Loans | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans	0
Total Past Due Loans | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans	14,645
Total Past Due Loans | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans	0
Total Past Due Loans | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans	5,751
Total Past Due Loans | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans	1,290
Total Past Due Loans | Agricultural
Financing Receivable, Past Due [Line Items]
Loans	16
Total Past Due Loans | Consumer
Financing Receivable, Past Due [Line Items]
Loans	225
Current Loans
Financing Receivable, Past Due [Line Items]
Loans	12,405,422
Loans, before deferred fees		13,030,214
Current Loans | Receivables Acquired with Deteriorated Credit Quality
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		210,943
Current Loans | Commercial
Financing Receivable, Past Due [Line Items]
Loans	1,971,789
Current Loans | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans	788,848
Current Loans | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans	6,602,810
Current Loans | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans	1,180,181
Current Loans | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans	1,294,371
Current Loans | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans	379,337
Current Loans | Agricultural
Financing Receivable, Past Due [Line Items]
Loans	106,496
Current Loans | Consumer
Financing Receivable, Past Due [Line Items]
Loans	$ 81,590
Receivables, excluding receivables acquired with deteriorated credit quality
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		12,861,309
Receivables, excluding receivables acquired with deteriorated credit quality | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		2,409,483
Receivables, excluding receivables acquired with deteriorated credit quality | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1,453,797
Receivables, excluding receivables acquired with deteriorated credit quality | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		5,940,947
Receivables, excluding receivables acquired with deteriorated credit quality | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1,230,543
Receivables, excluding receivables acquired with deteriorated credit quality | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1,347,784
Receivables, excluding receivables acquired with deteriorated credit quality | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		326,575
Receivables, excluding receivables acquired with deteriorated credit quality | Agricultural
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		84,897
Receivables, excluding receivables acquired with deteriorated credit quality | Consumer
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		67,283
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		10,951
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		3,243
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		0
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		2,434
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		19
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		5,169
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		0
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due | Agricultural
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		0
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 30-89 Days Past Due | Consumer
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		86
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		31,087
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		13,227
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		0
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		16,790
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		0
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1,028
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		0
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due | Agricultural
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1
Receivables, excluding receivables acquired with deteriorated credit quality | Loans 90 Days or More Past Due | Consumer
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		41
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		42,038
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		16,470
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		0
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		19,224
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		19
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		6,197
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		0
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans | Agricultural
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1
Receivables, excluding receivables acquired with deteriorated credit quality | Total Past Due Loans | Consumer
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		127
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		12,819,271
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		2,393,013
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans | Mortgage warehouse
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1,453,797
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans | Real estate | Commercial
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		5,921,723
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans | Real estate | Commercial construction, land and land development
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1,230,524
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans | Real estate | Residential Real Estate
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		1,341,587
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans | Real estate | Single-family interim construction
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		326,575
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans | Agricultural
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		84,896
Receivables, excluding receivables acquired with deteriorated credit quality | Current Loans | Consumer
Financing Receivable, Past Due [Line Items]
Loans, before deferred fees		$ 67,156

Loans, Net and Allowance for_10

Loans, Net and Allowance for Credit Losses on Loans - Loans held for investment by year of origination and internally assigned credit grade (Details) $ in Thousands	Dec. 31, 2021USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	$ 4,986,567
Term Loans by Year of Origination, 2020	2,062,363
Term Loans by Year of Origination, 2019	1,341,848
Term Loans by Year of Origination, 2018	1,061,979
Term Loans by Year of Origination, 2017	769,153
Term Loans by Year of Origination, Prior	1,208,460
Revolving Loans	990,512
Revolving Loans Converted to Term Loans	18,564
Total Loans	12,439,446
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	4,771,917
Term Loans by Year of Origination, 2020	1,995,309
Term Loans by Year of Origination, 2019	1,227,819
Term Loans by Year of Origination, 2018	933,094
Term Loans by Year of Origination, 2017	700,329
Term Loans by Year of Origination, Prior	1,051,269
Revolving Loans	930,290
Revolving Loans Converted to Term Loans	11,938
Total Loans	11,621,965
Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	73,849
Term Loans by Year of Origination, 2020	33,073
Term Loans by Year of Origination, 2019	49,665
Term Loans by Year of Origination, 2018	64,547
Term Loans by Year of Origination, 2017	45,251
Term Loans by Year of Origination, Prior	79,090
Revolving Loans	23,191
Revolving Loans Converted to Term Loans	4,638
Total Loans	373,304
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	61,990
Term Loans by Year of Origination, 2020	16,887
Term Loans by Year of Origination, 2019	46,416
Term Loans by Year of Origination, 2018	37,335
Term Loans by Year of Origination, 2017	20,003
Term Loans by Year of Origination, Prior	25,714
Revolving Loans	13,011
Revolving Loans Converted to Term Loans	0
Total Loans	221,356
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	78,811
Term Loans by Year of Origination, 2020	17,094
Term Loans by Year of Origination, 2019	17,948
Term Loans by Year of Origination, 2018	27,003
Term Loans by Year of Origination, 2017	3,570
Term Loans by Year of Origination, Prior	52,387
Revolving Loans	14,123
Revolving Loans Converted to Term Loans	1,988
Total Loans	212,924
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	9,897
Revolving Loans Converted to Term Loans	0
Total Loans	9,897
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	454,758
Term Loans by Year of Origination, 2020	187,165
Term Loans by Year of Origination, 2019	123,636
Term Loans by Year of Origination, 2018	88,830
Term Loans by Year of Origination, 2017	95,981
Term Loans by Year of Origination, Prior	278,180
Revolving Loans	744,798
Revolving Loans Converted to Term Loans	10,538
Total Loans	1,983,886
Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	422,810
Term Loans by Year of Origination, 2020	183,433
Term Loans by Year of Origination, 2019	98,059
Term Loans by Year of Origination, 2018	78,357
Term Loans by Year of Origination, 2017	81,620
Term Loans by Year of Origination, Prior	255,213
Revolving Loans	690,242
Revolving Loans Converted to Term Loans	5,231
Total Loans	1,814,965
Commercial | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	260
Term Loans by Year of Origination, 2020	3,010
Term Loans by Year of Origination, 2019	1,019
Term Loans by Year of Origination, 2018	3,135
Term Loans by Year of Origination, 2017	11,688
Term Loans by Year of Origination, Prior	65
Revolving Loans	18,768
Revolving Loans Converted to Term Loans	3,319
Total Loans	41,264
Commercial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	1,411
Term Loans by Year of Origination, 2020	117
Term Loans by Year of Origination, 2019	8,517
Term Loans by Year of Origination, 2018	7,244
Term Loans by Year of Origination, 2017	195
Term Loans by Year of Origination, Prior	4,571
Revolving Loans	12,885
Revolving Loans Converted to Term Loans	0
Total Loans	34,940
Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	30,277
Term Loans by Year of Origination, 2020	605
Term Loans by Year of Origination, 2019	16,041
Term Loans by Year of Origination, 2018	94
Term Loans by Year of Origination, 2017	2,478
Term Loans by Year of Origination, Prior	18,331
Revolving Loans	13,006
Revolving Loans Converted to Term Loans	1,988
Total Loans	82,820
Commercial | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	9,897
Revolving Loans Converted to Term Loans	0
Total Loans	9,897
Mortgage warehouse
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	788,848
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	788,848
Mortgage warehouse | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	788,848
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	788,848
Mortgage warehouse | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Mortgage warehouse | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Mortgage warehouse | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Mortgage warehouse | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Real estate | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	2,328,368
Term Loans by Year of Origination, 2020	1,249,987
Term Loans by Year of Origination, 2019	908,414
Term Loans by Year of Origination, 2018	748,288
Term Loans by Year of Origination, 2017	552,252
Term Loans by Year of Origination, Prior	750,840
Revolving Loans	73,667
Revolving Loans Converted to Term Loans	5,639
Total Loans	6,617,455
Real estate | Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	2,181,292
Term Loans by Year of Origination, 2020	1,198,508
Term Loans by Year of Origination, 2019	830,902
Term Loans by Year of Origination, 2018	645,470
Term Loans by Year of Origination, 2017	504,126
Term Loans by Year of Origination, Prior	626,292
Revolving Loans	71,850
Revolving Loans Converted to Term Loans	4,320
Total Loans	6,062,760
Real estate | Commercial | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	54,671
Term Loans by Year of Origination, 2020	18,591
Term Loans by Year of Origination, 2019	39,045
Term Loans by Year of Origination, 2018	60,955
Term Loans by Year of Origination, 2017	30,196
Term Loans by Year of Origination, Prior	74,762
Revolving Loans	752
Revolving Loans Converted to Term Loans	1,319
Total Loans	280,291
Real estate | Commercial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	56,142
Term Loans by Year of Origination, 2020	16,770
Term Loans by Year of Origination, 2019	37,331
Term Loans by Year of Origination, 2018	29,962
Term Loans by Year of Origination, 2017	17,649
Term Loans by Year of Origination, Prior	20,100
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	177,954
Real estate | Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	36,263
Term Loans by Year of Origination, 2020	16,118
Term Loans by Year of Origination, 2019	1,136
Term Loans by Year of Origination, 2018	11,901
Term Loans by Year of Origination, 2017	281
Term Loans by Year of Origination, Prior	29,686
Revolving Loans	1,065
Revolving Loans Converted to Term Loans	0
Total Loans	96,450
Real estate | Commercial | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Real estate | Commercial construction, land and land development
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	651,568
Term Loans by Year of Origination, 2020	272,595
Term Loans by Year of Origination, 2019	105,263
Term Loans by Year of Origination, 2018	100,085
Term Loans by Year of Origination, 2017	15,688
Term Loans by Year of Origination, Prior	16,396
Revolving Loans	18,586
Revolving Loans Converted to Term Loans	0
Total Loans	1,180,181
Real estate | Commercial construction, land and land development | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	618,288
Term Loans by Year of Origination, 2020	262,136
Term Loans by Year of Origination, 2019	98,007
Term Loans by Year of Origination, 2018	85,596
Term Loans by Year of Origination, 2017	13,751
Term Loans by Year of Origination, Prior	14,939
Revolving Loans	18,586
Revolving Loans Converted to Term Loans	0
Total Loans	1,111,303
Real estate | Commercial construction, land and land development | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	17,899
Term Loans by Year of Origination, 2020	10,459
Term Loans by Year of Origination, 2019	6,869
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	84
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	35,311
Real estate | Commercial construction, land and land development | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	3,780
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	1,909
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	5,689
Real estate | Commercial construction, land and land development | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	11,601
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	387
Term Loans by Year of Origination, 2018	14,489
Term Loans by Year of Origination, 2017	28
Term Loans by Year of Origination, Prior	1,373
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	27,878
Real estate | Commercial construction, land and land development | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Real estate | Residential Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	410,718
Term Loans by Year of Origination, 2020	268,003
Term Loans by Year of Origination, 2019	193,112
Term Loans by Year of Origination, 2018	115,669
Term Loans by Year of Origination, 2017	91,650
Term Loans by Year of Origination, Prior	158,067
Revolving Loans	60,559
Revolving Loans Converted to Term Loans	2,344
Total Loans	1,300,122
Real estate | Residential Real Estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	408,402
Term Loans by Year of Origination, 2020	267,147
Term Loans by Year of Origination, 2019	190,890
Term Loans by Year of Origination, 2018	114,616
Term Loans by Year of Origination, 2017	88,295
Term Loans by Year of Origination, Prior	149,871
Revolving Loans	60,212
Revolving Loans Converted to Term Loans	2,344
Total Loans	1,281,777
Real estate | Residential Real Estate | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	1,019
Term Loans by Year of Origination, 2020	487
Term Loans by Year of Origination, 2019	1,270
Term Loans by Year of Origination, 2018	405
Term Loans by Year of Origination, 2017	2,331
Term Loans by Year of Origination, Prior	4,179
Revolving Loans	169
Revolving Loans Converted to Term Loans	0
Total Loans	9,860
Real estate | Residential Real Estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	657
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	568
Term Loans by Year of Origination, 2018	129
Term Loans by Year of Origination, 2017	250
Term Loans by Year of Origination, Prior	1,043
Revolving Loans	126
Revolving Loans Converted to Term Loans	0
Total Loans	2,773
Real estate | Residential Real Estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	640
Term Loans by Year of Origination, 2020	369
Term Loans by Year of Origination, 2019	384
Term Loans by Year of Origination, 2018	519
Term Loans by Year of Origination, 2017	774
Term Loans by Year of Origination, Prior	2,974
Revolving Loans	52
Revolving Loans Converted to Term Loans	0
Total Loans	5,712
Real estate | Residential Real Estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Real estate | Single-family interim construction
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	305,267
Term Loans by Year of Origination, 2020	59,584
Term Loans by Year of Origination, 2019	2,801
Term Loans by Year of Origination, 2018	312
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	12,663
Revolving Loans Converted to Term Loans	0
Total Loans	380,627
Real estate | Single-family interim construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	305,267
Term Loans by Year of Origination, 2020	59,584
Term Loans by Year of Origination, 2019	2,801
Term Loans by Year of Origination, 2018	312
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	12,663
Revolving Loans Converted to Term Loans	0
Total Loans	380,627
Real estate | Single-family interim construction | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Real estate | Single-family interim construction | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Real estate | Single-family interim construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Real estate | Single-family interim construction | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	36,442
Term Loans by Year of Origination, 2020	15,531
Term Loans by Year of Origination, 2019	5,916
Term Loans by Year of Origination, 2018	8,085
Term Loans by Year of Origination, 2017	13,264
Term Loans by Year of Origination, Prior	4,779
Revolving Loans	22,495
Revolving Loans Converted to Term Loans	0
Total Loans	106,512
Agricultural | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	36,442
Term Loans by Year of Origination, 2020	15,005
Term Loans by Year of Origination, 2019	4,454
Term Loans by Year of Origination, 2018	8,033
Term Loans by Year of Origination, 2017	12,229
Term Loans by Year of Origination, Prior	4,773
Revolving Loans	18,993
Revolving Loans Converted to Term Loans	0
Total Loans	99,929
Agricultural | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	526
Term Loans by Year of Origination, 2019	1,462
Term Loans by Year of Origination, 2018	52
Term Loans by Year of Origination, 2017	1,035
Term Loans by Year of Origination, Prior	0
Revolving Loans	3,502
Revolving Loans Converted to Term Loans	0
Total Loans	6,577
Agricultural | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Agricultural | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	6
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	6
Agricultural | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	10,598
Term Loans by Year of Origination, 2020	9,498
Term Loans by Year of Origination, 2019	2,706
Term Loans by Year of Origination, 2018	710
Term Loans by Year of Origination, 2017	318
Term Loans by Year of Origination, Prior	198
Revolving Loans	57,744
Revolving Loans Converted to Term Loans	43
Total Loans	81,815
Consumer | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	10,568
Term Loans by Year of Origination, 2020	9,496
Term Loans by Year of Origination, 2019	2,706
Term Loans by Year of Origination, 2018	710
Term Loans by Year of Origination, 2017	308
Term Loans by Year of Origination, Prior	181
Revolving Loans	57,744
Revolving Loans Converted to Term Loans	43
Total Loans	81,756
Consumer | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	1
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	1
Consumer | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	0
Consumer | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	30
Term Loans by Year of Origination, 2020	2
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	9
Term Loans by Year of Origination, Prior	17
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	58
Consumer | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Term Loans by Year of Origination, 2021	0
Term Loans by Year of Origination, 2020	0
Term Loans by Year of Origination, 2019	0
Term Loans by Year of Origination, 2018	0
Term Loans by Year of Origination, 2017	0
Term Loans by Year of Origination, Prior	0
Revolving Loans	0
Revolving Loans Converted to Term Loans	0
Total Loans	$ 0

Loans, Net and Allowance for Lo

Loans, Net and Allowance for Loan Losses - Summary of Loans by Credit Quality Indicator (Details) $ in Thousands	Dec. 31, 2020USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	$ 13,076,095
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	12,006,267
Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	424,143
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	406,080
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	229,514
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	10,091
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	2,448,699
Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	2,247,059
Commercial | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	55,960
Commercial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	38,186
Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	97,403
Commercial | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	10,091
Mortgage warehouse
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,453,797
Mortgage warehouse | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,453,797
Mortgage warehouse | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Mortgage warehouse | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Mortgage warehouse | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Mortgage warehouse | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Real estate | Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	6,096,676
Real estate | Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	5,379,801
Real estate | Commercial | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	306,884
Real estate | Commercial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	317,580
Real estate | Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	92,411
Real estate | Commercial | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Real estate | Commercial construction, land and land development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,245,801
Real estate | Commercial construction, land and land development | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,125,132
Real estate | Commercial construction, land and land development | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	46,026
Real estate | Commercial construction, land and land development | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	43,383
Real estate | Commercial construction, land and land development | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	31,260
Real estate | Commercial construction, land and land development | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Real estate | Residential Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,352,465
Real estate | Residential Real Estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,332,757
Real estate | Residential Real Estate | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	6,296
Real estate | Residential Real Estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	5,726
Real estate | Residential Real Estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	7,686
Real estate | Residential Real Estate | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Real estate | Single-family interim construction
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	326,575
Real estate | Single-family interim construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	323,800
Real estate | Single-family interim construction | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	2,775
Real estate | Single-family interim construction | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Real estate | Single-family interim construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Real estate | Single-family interim construction | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	85,014
Agricultural | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	76,951
Agricultural | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	6,194
Agricultural | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	1,205
Agricultural | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	664
Agricultural | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	67,068
Consumer | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	66,970
Consumer | Pass/ Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	8
Consumer | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	0
Consumer | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	90
Consumer | Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, gross	$ 0

Premises and Equipment, Net - C

Premises and Equipment, Net - Components of Premises and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Land	$ 78,900	$ 65,103
Building	193,475	191,940
Furniture, fixtures and equipment	47,576	39,282
Aircraft	8,947	8,947
Leasehold and tenant improvements	5,834	5,798
Construction in progress	45,263	915
Premises and equipment, gross	379,995	311,985
Less accumulated depreciation	(71,972)	(62,518)
Premises and equipment, net	$ 308,023	$ 249,467

Premises and Equipment, Net - A

Premises and Equipment, Net - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 12,385	$ 12,728	$ 11,783

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets, Net - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 994,021	$ 994,021
Amortization of other intangible assets	$ 12,580	$ 12,671	$ 12,880
Remaining weighted averaged amortization period	6 years 6 months

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets, Net - Gross Carrying Value and Accumulated Amortization of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Acquired Finite-Lived Intangible Assets [Line Items]
Total other intangible assets, net	$ 75,490	$ 88,070
Core deposit intangibles
Acquired Finite-Lived Intangible Assets [Line Items]
Balance at end of the year	125,884	125,884
Less accumulated amortization	(55,323)	(43,235)
Total other intangible assets, net	70,561	82,649
Customer relationship intangibles
Acquired Finite-Lived Intangible Assets [Line Items]
Balance at end of the year	6,407	6,407
Less accumulated amortization	(1,478)	(986)
Total other intangible assets, net	$ 4,929	$ 5,421

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets, Net - Future Amortization Expense Related to Core Deposit Intangible (Detail) $ in Thousands	Dec. 31, 2021USD ($)
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
First year	$ 12,491
Second year	12,439
Third year	11,752
Fourth year	11,238
Fifth year	10,801
Thereafter	16,769
Future amortization expense	$ 75,490

Deposits - Components of Deposi

Deposits - Components of Deposits (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amount
Noninterest-bearing demand accounts	$ 5,066,588	$ 4,164,800
Interest-bearing checking accounts	6,234,344	5,420,548
Savings accounts	758,727	654,733
Money market accounts	2,431,965	2,743,208
Certificates of deposit and individual retirement accounts (IRA), less than $250,000	540,011	675,329
Certificates of deposit and individual retirement accounts (IRA), $250,000 and greater	522,273	740,309
Total deposits	$ 15,553,908	$ 14,398,927
Percent
Noninterest-bearing demand accounts (percent)	32.60%	28.90%
Interest-bearing checking accounts (percent)	40.10%	37.60%
Savings accounts (percent)	4.90%	4.60%
Limited access money market accounts (percent)	15.60%	19.10%
Certificates of deposit and individual retirement accounts (IRA), less than $250,000 (percent)	3.50%	4.70%
Certificates of deposit and individual retirement account (IRA), $250,000 and greater (percent)	3.30%	5.10%
Total deposits (percent)	100.00%	100.00%

Deposits - Maturities of Certif

Deposits - Maturities of Certificates of Deposit (Detail) $ in Thousands	Dec. 31, 2021USD ($)
Time Deposits, Fiscal Year Maturity [Abstract]
First year	$ 928,258
Second year	101,081
Third year	12,432
Fourth year	10,709
Fifth year	9,804
Total	$ 1,062,284

Deposits - Additional Informati

Deposits - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deposits [Abstract]
Brokered deposit	$ 909,665	$ 1,521,129

Federal Home Loan Bank Advanc_2

Federal Home Loan Bank Advances - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Weighted average interest rate on advances (percent)	0.48%	0.57%
Outstanding balances of advances	$ 150,000	$ 375,000
Federal Home Loan Bank Stock	18,546
Carrying value of loans with blanket lien	5,581,162
Remaining credit facility under FHLB advances	3,952,344
Federal Home Loan Bank Advances
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Undisbursed advance commitments (letter of credit)	$ 1,473,105

Other Borrowings - Other Borrow

Other Borrowings - Other Borrowings (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Other borrowings	$ 283,371,000	$ 312,175,000
Other borrowings, related parties	50,000	50,000
5.875% Subordinated Notes Due August 1, 2024
Debt Instrument [Line Items]
Subordinated debt	109,087,000	108,729,000
Debt original amount	$ 110,000,000	110,000,000
Stated interest rate (percent)	5.875%
Discount and origination costs	$ 913,000	1,271,000
5.75% Subordinated Debenture Notes Due July 20, 2026
Debt Instrument [Line Items]
Subordinated debt	0	40,000,000
Debt original amount	$ 40,000,000	40,000,000
Stated interest rate (percent)	5.75%
5.00% Subordinated Debenture Notes Due December 31, 2027
Debt Instrument [Line Items]
Subordinated debt	$ 29,535,000	29,457,000
Debt original amount	$ 30,000,000	30,000,000
Stated interest rate (percent)	5.00%
Origination costs	$ 465,000	543,000
Unsecured Subordinated Debenture Notes Due September 15, 2030
Debt Instrument [Line Items]
Subordinated debt	127,749,000	127,489,000
Debt original amount	$ 130,000,000	130,000,000
Stated interest rate (percent)	4.00%
Origination costs	$ 2,251,000	2,511,000
London Interbank Offered Rate (LIBOR) | 5.75% Subordinated Debenture Notes Due July 20, 2026
Debt Instrument [Line Items]
Basis spread on variable rate	4.73%
London Interbank Offered Rate (LIBOR) | 5.00% Subordinated Debenture Notes Due December 31, 2027
Debt Instrument [Line Items]
Basis spread on variable rate	2.83%
Secured Overnight Financing Rate (SOFR) | Unsecured Subordinated Debenture Notes Due September 15, 2030
Debt Instrument [Line Items]
Basis spread on variable rate	3.885%
Line of Credit | Line of Credit | Revolving line of credit
Debt Instrument [Line Items]
Line of Credit Facility, Outstanding Balance	$ 17,000,000	$ 6,500,000
Line of credit, maximum capacity	$ 100,000,000
Line of Credit | Line of Credit | London Interbank Offered Rate (LIBOR) | Revolving line of credit
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%

Other Borrowings - Additional I

Other Borrowings - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2021USD ($)Number_of_Linesunaffiliated_bank	Dec. 31, 2020USD ($)unaffiliated_bank
Federal Funds Line of Credit | Line of Credit
Line of Credit Facility [Line Items]
Line of credit, maximum capacity	$ 400,000,000	$ 365,000,000
Outstanding borrowings on line of credit	$ 0	$ 0
Number of unaffiliated banks | unaffiliated_bank	11	9
Secured Debt | Line of Credit
Line of Credit Facility [Line Items]
Line of credit, maximum capacity	$ 851,051,000	$ 716,700,000
Outstanding borrowings on line of credit	0	0
Line of credit, collateral	1,195,362,000	1,034,467,000
Unsecured Debt | Direct Overnight Borrowings | Line of Credit
Line of Credit Facility [Line Items]
Line of credit, maximum capacity	814,000,000	694,000,000
Outstanding borrowings on line of credit	0	$ 0
Line of Credit | Federal Funds Line of Credit
Line of Credit Facility [Line Items]
Line of credit, maximum capacity	$ 30,000,000
Number of lines | Number_of_Lines	2

Junior Subordinated Debenture_2

Junior Subordinated Debentures - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)business_trust	Dec. 31, 2020USD ($)
Debt Instrument [Line Items]
Number of wholly owned statutory business trusts | business_trust	9
Trust Preferred Securities Issued	$ 57,324
Junior subordinated debentures, carrying value	54,221	$ 54,023
Junior subordinated debentures, unamortized discount	3,103
IB Trust I
Debt Instrument [Line Items]
Trust Preferred Securities Issued	5,155
Junior subordinated debentures, carrying value	$ 5,155
Interest Rate	3.38%
Guaranty Trust III
Debt Instrument [Line Items]
Trust Preferred Securities Issued	$ 10,310
Junior subordinated debentures, carrying value	$ 10,310
Interest Rate	3.22%
IB Trust II
Debt Instrument [Line Items]
Trust Preferred Securities Issued	$ 3,093
Junior subordinated debentures, carrying value	$ 3,093
Interest Rate	2.97%
Cenbank Trust III
Debt Instrument [Line Items]
Trust Preferred Securities Issued	$ 15,464
Junior subordinated debentures, carrying value	$ 15,464
Interest Rate	2.77%
IB Trust III
Debt Instrument [Line Items]
Trust Preferred Securities Issued	$ 3,712
Junior subordinated debentures, carrying value	$ 3,712
Interest Rate	2.56%
IB Centex Trust I
Debt Instrument [Line Items]
Trust Preferred Securities Issued	$ 2,578
Junior subordinated debentures, carrying value	$ 2,578
Interest Rate	3.41%
Community Group Statutory Trust I
Debt Instrument [Line Items]
Trust Preferred Securities Issued	$ 3,609
Junior subordinated debentures, carrying value	$ 3,609
Interest Rate	1.80%
Northstar Trust II
Debt Instrument [Line Items]
Trust Preferred Securities Issued	$ 5,155
Junior subordinated debentures, carrying value	$ 3,969
Interest Rate	1.87%
Northstar Trust III
Debt Instrument [Line Items]
Trust Preferred Securities Issued	$ 8,248
Junior subordinated debentures, carrying value	$ 6,331
Interest Rate	1.87%
London Interbank Offered Rate (LIBOR) | IB Trust I
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	3.25%
London Interbank Offered Rate (LIBOR) | Guaranty Trust III
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	3.10%
London Interbank Offered Rate (LIBOR) | IB Trust II
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	2.85%
London Interbank Offered Rate (LIBOR) | Cenbank Trust III
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	2.65%
London Interbank Offered Rate (LIBOR) | IB Trust III
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	2.40%
London Interbank Offered Rate (LIBOR) | IB Centex Trust I
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	3.25%
London Interbank Offered Rate (LIBOR) | Community Group Statutory Trust I
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	1.60%
London Interbank Offered Rate (LIBOR) | Northstar Trust II
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	1.67%
London Interbank Offered Rate (LIBOR) | Northstar Trust III
Debt Instrument [Line Items]
Description of variable rate basis	LIBOR
Interest Rate Index	1.67%

Leases - Additional Information

Leases - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)branch	Dec. 31, 2020USD ($)
Lessee, Lease, Description [Line Items]
Number of branches leased | branch	21
Number of branches operated | branch	93
Right-of-use assets | $	$ 24,126	$ 24,841
Lease liability | $	$ 23,573	$ 23,413
Minimum
Lessee, Lease, Description [Line Items]
Operating leases, remaining term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating leases, remaining term	29 years

Leases - Schedule of Net Lease

Leases - Schedule of Net Lease Cost and Other Information Related to Operating Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease cost	$ 6,567	$ 6,937	$ 7,025
Short term lease cost	64	124	103
Variable lease cost	1,645	1,631	1,829
Sublease income	(282)	(221)	(228)
Net lease cost	7,994	8,471	$ 8,729
Operating cash flows from operating leases	$ 5,740	$ 6,091
Weighted average remaining lease term - operating leases, in years	7 years 4 months 28 days	7 years 2 months 23 days
Weighted average discount rate - operating leases	3.01%	3.47%

Leases - Summary of Lease Liabi

Leases - Summary of Lease Liability Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
2022	$ 5,308
2023	4,704
2024	4,109
2025	3,328
2026	1,882
Thereafter	6,921
Total lease payments	26,252
Less imputed interest	(2,679)
Lease liability	$ 23,573	$ 23,413

Income Taxes - Tax Expense (Det

Income Taxes - Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Current income tax expense	$ 52,130	$ 52,806	$ 39,426
Deferred income tax expense (benefit)	5,353	(1,633)	14,102
Income tax expense, as reported	$ 57,483	$ 51,173	$ 53,528

Income Taxes - Tax Reconciliati

Income Taxes - Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income tax expense computed at the statutory rate	$ 59,269	$ 53,000	$ 51,715
Tax-exempt interest income from municipal securities	(1,752)	(1,779)	(1,781)
Tax-exempt loan income	(1,359)	(1,245)	(1,174)
Bank owned life insurance income	(1,094)	(1,123)	(1,288)
Non-deductible acquisition expenses	0	0	281
State taxes, net of federal benefit	2,516	2,660	3,455
Non-deductible compensation	473	0	2,017
Net tax expense (benefit) from stock based compensation	(691)	243	21
Other	121	(583)	282
Income tax expense, as reported	$ 57,483	$ 51,173	$ 53,528

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Jan. 01, 2021	Dec. 31, 2020
Deferred tax assets:
Allowance for loan losses	$ 33,463	$ 15,113	$ 19,238
Lease liabilities under operating leases	5,141		5,129
NOL and tax credit carryforwards from acquisitions	3,354		3,718
Net unrealized loss on cash flow hedge	221		0
Acquired loan fair market value adjustments	5,750		12,986
Stock-based compensation	1,822		1,567
Reserve for bonuses and other accrued expenses	3,775		3,409
Deferred loan fees and costs, net	2,800		0
Acquired securities	1,611		2,095
Acquired intangibles	1,213		1,369
Start up costs	117		171
Unearned income	503		715
Deferred compensation	628		857
Noncompete agreements	540		597
Nonaccrual loans	463		550
Other	546		727
Deferred tax assets, gross	61,947		53,128
Deferred tax liabilities:
Premises and equipment	(10,376)		(12,392)
Right-of-use assets under operating leases	(4,934)		(4,911)
Net unrealized gain on available for sale securities	(1,457)		(9,501)
Intangible assets	(16,464)		(19,293)
Acquired junior subordinated debentures fair value adjustment	(677)		(723)
PPP deferred loan costs	(192)		(952)
FHLB and other restricted stocks	(335)		(308)
Acquired tax goodwill	(735)		(572)
Other	(599)		(543)
Deferred tax liabilities, gross	(35,769)		(49,195)
Net deferred tax asset	$ 26,178		$ 3,933

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Operating Loss Carryforwards [Line Items]
Valuation allowance	$ 0	$ 0
Federal Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	14,237,000
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 10,146,000

Off-Balance Sheet Arrangement_3

Off-Balance Sheet Arrangements, Commitments and Contingencies (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Financial instruments with off-balance sheet risk	$ 2,800,043	$ 2,294,133
Commitments to extend credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Financial instruments with off-balance sheet risk	2,770,036	2,268,216
Standby letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Financial instruments with off-balance sheet risk	$ 30,007	$ 25,917

Off-Balance Sheet Arrangement_4

Off-Balance Sheet Arrangements, Commitments and Contingencies - Allowance for Off-Balance Sheet Credit Exposure (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	$ 0	$ 0	$ 0
Provision for off-balance sheet credit exposure	3,609	0	0
Balance at end of period	4,722	0	0
Cumulative effect of change in accounting principle
Off-Balance Sheet, Credit Loss, Liability [Roll Forward]
Balance at beginning of period	$ 1,113	0	0
Balance at end of period		$ 1,113	$ 0

Related Party Transactions - Lo

Related Party Transactions - Loan Activity for Officers, Directors and Affiliates (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)
Loans and Leases Receivable, Related Parties [Roll Forward]
Balance at beginning of year	$ 32,471
New loan originations	30,977
Repayments	(21,596)
Changes in affiliated persons	(7,225)
Balance at end of year	$ 34,627

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Retirement Benefits [Abstract]
Minimum age	18 years
Credited service period	30 days
Salary reduction set by law	$ 19,500
Employer contribution, matching percentage (percent)	100.00%	100.00%	100.00%
Employer contribution as percentage of participant's eligible salary (percent)	6.00%	6.00%	6.00%
Employer contribution, amount	$ 7,011,000	$ 6,534,000	$ 6,343,000

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities at Fair Value on Recurring Basis (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	$ 2,006,727,000	$ 1,153,693,000
Loans held for sale, fair value option elected	28,249,000	71,769,000
Aggregate principal balance of loans held for sale	27,176,000	68,670,000
Loans held for sale, 90 days or greater past due	0
Loans held for sale, non-accrual	0
Derivatives not designated as hedging instruments | Interest rate lock commitments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	1,029,000	3,515,000
Liability Derivative Fair Value	4,000	0
Derivatives not designated as hedging instruments | Forward mortgage-backed securities trades
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	27,000	0
Liability Derivative Fair Value	21,000	568,000
Derivatives designated as hedging instruments | Interest rate swaps - cash flow hedge
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0
Liability Derivative Fair Value	1,158,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Loans held for sale, fair value option elected	28,249,000	71,769,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Loans held for sale, fair value option elected	0	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Loans held for sale, fair value option elected	28,249,000	71,769,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Loans held for sale, fair value option elected	0	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate lock commitments
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	1,029,000	3,515,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate lock commitments | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate lock commitments | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	1,029,000	3,515,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate lock commitments | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Forward mortgage-backed securities trades
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	27,000
Liability Derivative Fair Value	21,000	568,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Forward mortgage-backed securities trades | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0
Liability Derivative Fair Value	0	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Forward mortgage-backed securities trades | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	27,000
Liability Derivative Fair Value	21,000	568,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Forward mortgage-backed securities trades | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0
Liability Derivative Fair Value	0	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Liability Derivative Fair Value	4,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Liability Derivative Fair Value	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Liability Derivative Fair Value	4,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Liability Derivative Fair Value	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Loan customer counterparty
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	6,459,000	20,159,000
Liability Derivative Fair Value	1,073,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Loan customer counterparty | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0	0
Liability Derivative Fair Value	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Loan customer counterparty | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	6,459,000	20,159,000
Liability Derivative Fair Value	1,073,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Loan customer counterparty | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0	0
Liability Derivative Fair Value	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Financial institution counterparty
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	1,078,000
Liability Derivative Fair Value	6,772,000	21,306,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Financial institution counterparty | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0
Liability Derivative Fair Value	0	0
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Financial institution counterparty | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	1,078,000
Liability Derivative Fair Value	6,772,000	21,306,000
Fair Value, Measurements, Recurring | Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Financial institution counterparty | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Asset Derivative Fair Value	0
Liability Derivative Fair Value	0	0
Fair Value, Measurements, Recurring | Derivatives designated as hedging instruments | Interest rate swaps - cash flow hedge
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Liability Derivative Fair Value	1,158,000
Fair Value, Measurements, Recurring | Derivatives designated as hedging instruments | Interest rate swaps - cash flow hedge | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Liability Derivative Fair Value	0
Fair Value, Measurements, Recurring | Derivatives designated as hedging instruments | Interest rate swaps - cash flow hedge | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Liability Derivative Fair Value	1,158,000
Fair Value, Measurements, Recurring | Derivatives designated as hedging instruments | Interest rate swaps - cash flow hedge | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Liability Derivative Fair Value	0
U.S. treasuries
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	174,996,000	44,708,000
U.S. treasuries | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	174,996,000	44,708,000
U.S. treasuries | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
U.S. treasuries | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	174,996,000	44,708,000
U.S. treasuries | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Government agency securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	444,675,000	249,017,000
Government agency securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	444,675,000	249,017,000
Government agency securities | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Government agency securities | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	444,675,000	249,017,000
Government agency securities | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Obligations of state and municipal subdivisions
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	432,760,000	393,165,000
Obligations of state and municipal subdivisions | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	432,760,000	393,165,000
Obligations of state and municipal subdivisions | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Obligations of state and municipal subdivisions | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	432,760,000	393,165,000
Obligations of state and municipal subdivisions | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	34,796,000	22,102,000
Corporate bonds | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	34,796,000	22,102,000
Corporate bonds | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Corporate bonds | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	34,796,000	22,102,000
Corporate bonds | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	918,550,000	443,501,000
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	918,550,000	443,501,000
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	918,550,000	443,501,000
Mortgage-backed securities guaranteed by FHLMC, FNMA and GNMA | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Other securities
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	950,000	1,200,000
Other securities | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	950,000	1,200,000
Other securities | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	0	0
Other securities | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	950,000	1,200,000
Other securities | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Securities available for sale	$ 0	$ 0

Fair Value Measurements - Ass_2

Fair Value Measurements - Assets and Liabilities at Fair Value on Nonrecurring Basis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Individually evaluated loans	$ 64,944	$ 64,383
Fair Value, Measurements, Nonrecurring
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Individually evaluated loans	11,204	16,903
Other real estate owned	0	0
Fair Value, Measurements, Nonrecurring | Individually evaluated loans
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Period Ended Total Losses	3,526	13,041
Fair Value, Measurements, Nonrecurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Individually evaluated loans	0	0
Fair Value, Measurements, Nonrecurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Individually evaluated loans	0	0
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Individually evaluated loans	$ 11,204	$ 16,903

Fair Value Measurements - Carry

Fair Value Measurements - Carrying Amount and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	$ 2,800,043	$ 2,294,133
Commitments to extend credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	2,770,036	2,268,216
Standby letters of credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	30,007	25,917
Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial assets:
Cash and cash equivalents	2,608,444	1,813,987
Certificates of deposit held in other banks	0	0
Loans held for sale, at cost	0	0
Loans, net	0	0
FHLB of Dallas stock and other restricted stock	0	0
Accrued interest receivable	0	0
Financial liabilities:
Deposits	0	0
Accrued interest payable	0	0
FHLB advances	0	0
Other borrowings	0	0
Junior subordinated debentures	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Commitments to extend credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Standby letters of credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Significant Other Observable Inputs (Level 2)
Financial assets:
Cash and cash equivalents	0	0
Certificates of deposit held in other banks	3,246	4,595
Loans held for sale, at cost	3,982	11,138
Loans, net	0	0
FHLB of Dallas stock and other restricted stock	21,573	20,305
Accrued interest receivable	49,636	60,581
Financial liabilities:
Deposits	15,553,645	14,407,596
Accrued interest payable	5,301	7,397
FHLB advances	128,555	371,175
Other borrowings	303,250	327,150
Junior subordinated debentures	45,501	42,624
Significant Other Observable Inputs (Level 2) | Commitments to extend credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Significant Other Observable Inputs (Level 2) | Standby letters of credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Significant Unobservable Inputs (Level 3)
Financial assets:
Cash and cash equivalents	0	0
Certificates of deposit held in other banks	0	0
Loans held for sale, at cost	0	0
Loans, net	12,415,366	13,093,698
FHLB of Dallas stock and other restricted stock	0	0
Accrued interest receivable	0	0
Financial liabilities:
Deposits	0	0
Accrued interest payable	0	0
FHLB advances	0	0
Other borrowings	0	0
Junior subordinated debentures	0	0
Significant Unobservable Inputs (Level 3) | Commitments to extend credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Significant Unobservable Inputs (Level 3) | Standby letters of credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Carrying Amount
Financial assets:
Cash and cash equivalents	2,608,444	1,813,987
Certificates of deposit held in other banks	3,245	4,482
Loans held for sale, at cost	3,875	10,878
Loans, net	12,290,740	12,978,238
FHLB of Dallas stock and other restricted stock	21,573	20,305
Accrued interest receivable	49,636	60,581
Financial liabilities:
Deposits	15,553,908	14,398,927
Accrued interest payable	5,301	7,397
FHLB advances	150,000	375,000
Other borrowings	283,371	312,175
Junior subordinated debentures	54,221	54,023
Carrying Amount | Commitments to extend credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Carrying Amount | Standby letters of credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Estimated Fair Value
Financial assets:
Cash and cash equivalents	2,608,444	1,813,987
Certificates of deposit held in other banks	3,246	4,595
Loans held for sale, at cost	3,982	11,138
Loans, net	12,415,366	13,093,698
FHLB of Dallas stock and other restricted stock	21,573	20,305
Accrued interest receivable	49,636	60,581
Financial liabilities:
Deposits	15,553,645	14,407,596
Accrued interest payable	5,301	7,397
FHLB advances	128,555	371,175
Other borrowings	303,250	327,150
Junior subordinated debentures	45,501	42,624
Estimated Fair Value | Commitments to extend credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	0	0
Estimated Fair Value | Standby letters of credit
Off-balance sheet assets (liabilities):
Financial instruments with off-balance sheet risk	$ 0	$ 0

Derivative Financial Instrume_3

Derivative Financial Instruments - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Cash collateral pledged for derivatives	$ 20,491,000	$ 23,829,000
Securities collateral pledged for derivatives	3,168,000	$ 6,494,000
Interest rate swaps - cash flow hedge | Loan customer counterparty
Derivative [Line Items]
Credit exposure	7,537,000
Interest rate swaps - cash flow hedge | Derivatives designated as hedging instruments
Derivative [Line Items]
Outstanding Notional Balance	100,000,000
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	513,000
Interest rate swaps - cash flow hedge | Derivatives designated as hedging instruments | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Derivative [Line Items]
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax	359,000
Interest Rate Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	$ 472,000
Risk Participation Agreements Participant Bank
Derivative [Line Items]
Number of risk participation agreements	1
Credit risk participation	$ 5,121,000
Risk Participation Agreements Lead Bank
Derivative [Line Items]
Number of risk participation agreements	1
Credit risk participation	$ 9,348,000

Derivative Financial Instrume_4

Derivative Financial Instruments - Notional Balances and Fair Values of Outstanding Positions (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Derivatives not designated as hedging instruments | Interest rate lock commitments
Derivative [Line Items]
Outstanding Notional Balance	$ 34,064	$ 116,795
Asset Derivative Fair Value	1,029	3,515
Liability Derivative Fair Value	4	0
Derivatives not designated as hedging instruments | Forward mortgage-backed securities trades
Derivative [Line Items]
Outstanding Notional Balance	30,500	104,000
Asset Derivative Fair Value	27	0
Liability Derivative Fair Value	21	568
Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Commercial loan interest rate swaps: | Loan customer counterparty
Derivative [Line Items]
Outstanding Notional Balance	254,935	335,370
Asset Derivative Fair Value	6,459	20,159
Liability Derivative Fair Value	1,073	0
Derivatives not designated as hedging instruments | Interest rate swaps - cash flow hedge | Commercial loan interest rate swaps: | Financial institution counterparty
Derivative [Line Items]
Outstanding Notional Balance	254,935	335,370
Asset Derivative Fair Value	1,078	0
Liability Derivative Fair Value	6,772	$ 21,306
Derivatives designated as hedging instruments | Interest rate swaps - cash flow hedge
Derivative [Line Items]
Outstanding Notional Balance	100,000
Asset Derivative Fair Value	0
Liability Derivative Fair Value	$ 1,158

Derivative Financial Instrume_5

Derivative Financial Instruments Derivative Financial Instruments - Schedule of Weighted Average Interest Rate Received and Paid (Details) - Derivatives not designated as hedging instruments - Commercial loan interest rate swaps: - Loan customer counterparty - Interest rate swaps - cash flow hedge	Dec. 31, 2021	Dec. 31, 2020
Interest Rate Received
Derivative [Line Items]
Derivative Weighted Average Fixed Interest Rate (Received)	4.12%	4.08%
Interest Rate Paid
Derivative [Line Items]
Derivative Weighted Average Variable Interest Rate (Paid)	2.40%	2.32%

Derivative Financial Instrume_6

Derivative Financial Instruments - Income (Loss) on Derivatives Not Designated as Hedging Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Interest rate swaps - cash flow hedge | Derivatives designated as hedging instruments
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 584	$ 0	$ 0
Interest rate lock commitments | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(2,490)	2,668	25
Forward mortgage-backed securities trades | Derivatives not designated as hedging instruments
Derivative [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 574	$ (505)	$ 163

Stock Awards - Additional Infor

Stock Awards - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 8,984,000	$ 8,450,000	$ 7,808,000
Estimated future compensation expense	$ 12,700,000
Period for recognition	2 years 2 months 19 days
Fair value of common stock awards vested	$ 12,651,000	5,602,000	8,725,000
Stock based compensation expense	10,691,000	8,450,000	7,808,000
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax expense (benefit) on vested restricted stock	$ (691,000)	243,000	$ 21,000
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period for recognition	2 years 5 months 26 days
Stock based compensation expense	$ 1,707,000	$ 0
Unrecognized compensation expense	3,323,000
Maximum | Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 5,838,000
2013 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (shares)				2,300,000
Remaining available for grant for future awards (shares)	1,070,419
2013 Equity Incentive Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock vesting period	1 year
2013 Equity Incentive Plan | Minimum | Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock vesting period	3 years
Stock based compensation, award vesting percentage	0.00%
2013 Equity Incentive Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock vesting period	5 years
2013 Equity Incentive Plan | Maximum | Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock vesting period	4 years
Stock based compensation, award vesting percentage	150.00%

Stock Awards - Nonvested Restri

Stock Awards - Nonvested Restricted Stock Awards Activity (Details) - Restricted stock - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Number of Shares
Nonvested shares, beginning balance (shares)	468,800	284,861
Granted during the period (shares)	115,463	310,290
Vested during the period (shares)	(185,447)	(115,436)
Forfeited during the period (shares)	(35,265)	(10,915)
Nonvested shares, ending balance (shares)	363,551	468,800
Weighted Average Grant Date Fair Value
Nonvested shares, beginning balance (usd per share)	$ 49.01	$ 58.63
Granted during the period (usd per share)	66.10	43.54
Vested during the period (usd per share)	51.18	58.08
Forfeited during the period (use per share)	50.23	48.37
Nonvested shares, ending balance (usd per share)	$ 53.14	$ 49.01

Stock Awards - Future Vesting S

Stock Awards - Future Vesting Schedule of Nonvested Shares (Detail)	Dec. 31, 2021shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares	363,551
First year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares	158,463
Second year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares	118,975
Third year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares	77,350
Fourth year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested shares	8,763

Stock Awards - Schedule of Nonv

Stock Awards - Schedule of Nonvested Restricted Stock Awards (Details) - Performance stock units - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Number of Shares
Nonvested shares, beginning balance (shares)	89,300	0
Granted during the period (shares)	25,198	89,300
Nonvested shares, ending balance (shares)	114,498	89,300
Weighted Average Grant Date Fair Value
Nonvested shares, beginning balance (usd per share)	$ 38.29	$ 0
Granted during the period (usd per share)	63.92	38.29
Nonvested shares, ending balance (usd per share)	$ 43.93	$ 38.29

Regulatory Matters - Additional

Regulatory Matters - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Oct. 22, 2020	Dec. 31, 2018
Regulatory Assets [Line Items]
Cumulative effect reduction to retained earnings	$ (2,576,650,000)	$ (2,515,371,000)	$ (2,339,773,000)		$ (1,606,433,000)
Common stock repurchased	$ 32,132,000	$ 5,819,000	$ 51,659,000
October 2020 Share Repurchase Program
Regulatory Assets [Line Items]
Stock repurchase authorized amount				$ 150,000,000
Common stock repurchased (shares)	419,098
Common stock repurchased	$ 29,241,000
October 2018 Share Repurchase Program
Regulatory Assets [Line Items]
Common stock repurchased (shares)		109,548
Common stock repurchased		$ 5,660,000
Common stock purchased to settle employee tax withholding related to vesting of stock awards (shares)	41,970	2,951
Common stock purchased to settle employee tax withholding related to vesting of stock awards	$ 2,891,000	$ 159,000
2022 Share Repurchase Program
Regulatory Assets [Line Items]
Stock repurchase authorized amount	$ 160,000,000

Regulatory Matters - Actual Cap

Regulatory Matters - Actual Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Consolidated
Total capital to risk weighted assets:
Actual Amount	$ 1,916,163	$ 1,825,661
Actual Ratio (percent)	0.1367	0.1332
Minimum Required for Capital Adequacy Purposes Amount	$ 1,471,510	$ 1,438,939
Minimum Required for Capital Adequacy Purposes Ratio (percent)	0.1050	0.1050
Tier 1 capital to risk weighted assets:
Tier One Risk Based Capital	$ 1,614,372	$ 1,471,841
Actual Ratio (percent)	0.1152	0.1074
Minimum Required for Capital Adequacy Purposes Amount	$ 1,191,223	$ 1,164,855
Minimum Required for Capital Adequacy Purposes Ratio (percent)	0.0850	0.0850
Common equity tier 1 to risk weighted assets:
Actual amount	$ 1,558,772	$ 1,416,241
Actual ratio (percent)	0.1112	0.1033
Minimum Required for Capital Adequacy Purposes Amount	$ 981,007	$ 959,293
Minimum Required for Capital Adequacy Purposes Ratio (percent)	0.0700	0.0700
Tier 1 capital to average assets:
Actual Amount	$ 1,614,372	$ 1,471,841
Actual Ratio (percent)	0.0880	0.0912
Minimum Required for Capital Adequacy Purposes Amount	$ 733,954	$ 645,730
Minimum Required for Capital Adequacy Purposes Ratio (percent)	0.0400	0.0400
Bank
Total capital to risk weighted assets:
Actual Amount	$ 1,983,530	$ 1,864,240
Actual Ratio (percent)	0.1416	0.1361
Minimum Required for Capital Adequacy Purposes Amount	$ 1,471,036	$ 1,438,385
Minimum Required for Capital Adequacy Purposes Ratio (percent)	0.1050	0.1050
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 1,400,987	$ 1,369,891
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (percent)	0.1000	0.1000
Tier 1 capital to risk weighted assets:
Tier One Risk Based Capital	$ 1,885,739	$ 1,776,420
Actual Ratio (percent)	0.1346	0.1297
Minimum Required for Capital Adequacy Purposes Amount	$ 1,190,839	$ 1,164,407
Minimum Required for Capital Adequacy Purposes Ratio (percent)	0.0850	0.0850
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 1,120,790	$ 1,095,913
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (percent)	0.0800	0.0800
Common equity tier 1 to risk weighted assets:
Actual amount	$ 1,885,739	$ 1,776,420
Actual ratio (percent)	0.1346	0.1297
Minimum Required for Capital Adequacy Purposes Amount	$ 980,691	$ 958,924
Minimum Required for Capital Adequacy Purposes Ratio (percent)	0.0700	0.0700
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 910,642	$ 890,429
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (percent)	0.0650	0.0650
Tier 1 capital to average assets:
Actual Amount	$ 1,885,739	$ 1,776,420
Actual Ratio (percent)	0.1028	0.1101
Minimum Required for Capital Adequacy Purposes Amount	$ 733,785	$ 645,539
Minimum Required for Capital Adequacy Purposes Ratio (percent)	0.0400	0.0400
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 917,231	$ 806,924
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio (percent)	0.0500	0.0500

Parent Company Only Financial_3

Parent Company Only Financial Statements - Balance Sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 2,608,444	$ 1,813,987
Other assets	130,446	143,730
Total assets	18,732,648	17,753,476
Liabilities and Stockholders’ Equity
Other borrowings	283,371	312,175
Junior subordinated debentures	54,221	54,023
Other liabilities	114,498	97,980
Total liabilities	16,155,998	15,238,105
Stockholders’ equity:
Preferred stock	0	0
Common stock	428	431
Additional paid-in capital	1,945,497	1,934,807
Retained earnings	625,484	543,800
Accumulated other comprehensive income	5,241	36,333
Total stockholders’ equity	2,576,650	2,515,371	$ 2,339,773	$ 1,606,433
Total liabilities and stockholders’ equity	18,732,648	17,753,476
Parent
Assets
Cash and cash equivalents	10,747	5,482	$ 8,277	$ 8,355
Investment in subsidiaries	2,904,395	2,876,171
Investment in trusts	1,724	1,724
Other assets	3,039	3,849
Total assets	2,919,905	2,887,226
Liabilities and Stockholders’ Equity
Other borrowings	283,371	312,175
Junior subordinated debentures	54,221	54,023
Other liabilities	5,663	5,657
Total liabilities	343,255	371,855
Stockholders’ equity:
Preferred stock	0	0
Common stock	428	431
Additional paid-in capital	1,945,497	1,934,807
Retained earnings	625,484	543,800
Accumulated other comprehensive income	5,241	36,333
Total stockholders’ equity	2,576,650	2,515,371
Total liabilities and stockholders’ equity	$ 2,919,905	$ 2,887,226

Parent Company Only Financial_4

Parent Company Only Financial Statements - Statement of Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Interest expense:
Interest on other borrowings	$ 15,247	$ 12,462	$ 11,590
Interest on junior subordinated debentures	1,756	2,162	3,028
Total interest expense	63,240	95,060	148,175
Noninterest income:
Other	12,987	19,216	22,216
Total noninterest income	66,517	85,063	78,176
Noninterest expense:
Salaries and employee benefits	180,336	157,540	162,683
Professional fees	15,530	12,630	7,936
Acquisition expense, including legal	0	16,225	33,445
Other	35,151	34,146	39,207
Total noninterest expense	313,606	306,134	321,864
Income tax benefit	(57,483)	(51,173)	(53,528)
Net income	224,750	201,209	192,736
Parent
Interest expense:
Interest on other borrowings	15,247	12,446	11,561
Interest on junior subordinated debentures	1,756	2,162	3,028
Total interest expense	17,003	14,608	14,589
Noninterest income:
Dividends from subsidiaries	134,547	83,314	105,877
Other	61	0	1
Total noninterest income	134,608	83,314	105,878
Noninterest expense:
Salaries and employee benefits	10,546	8,346	7,653
Professional fees	126	202	264
Acquisition expense, including legal	0	16,225	33,445
Other	2,510	2,424	2,562
Total noninterest expense	13,182	27,197	43,924
Income before income tax benefit and equity in undistributed income of subsidiaries	104,423	41,509	47,365
Income tax benefit	7,131	9,410	11,066
Income before equity in undistributed income of subsidiaries	111,554	50,919	58,431
Equity in undistributed income of subsidiaries	113,196	150,290	134,305
Net income	$ 224,750	$ 201,209	$ 192,736

Parent Company Only Financial_5

Parent Company Only Financial Statements - Statement of Cash Flows (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income	$ 224,750	$ 201,209	$ 192,736
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of discount and origination costs on borrowings	894	720	633
Stock based compensation expense	10,691	8,450	7,808
Excess tax (benefit) expense on restricted stock vested	(691)	243	21
Deferred tax expense (benefit)	5,353	(1,633)	14,102
Net change in other assets	14,293	(35,025)	(5,878)
Net change in other liabilities	(23,356)	(7,833)	(15,636)
Net cash provided by operating activities	277,433	154,295	173,319
Cash flows from investing activities:
Cash acquired in connection with acquisition	0	0	39,913
Cash paid in connection with acquisition	0	0	(9)
Net cash (used in) provided by investing activities	(294,464)	(1,471,388)	(673,988)
Cash flows from financing activities:
Proceeds from other borrowings	75,000	156,489	65,000
Repayments of other borrowings	(104,500)	(47,086)	(40,500)
Offering costs paid in connection with acquired bank	0	0	(804)
Repurchase of common stock	(32,132)	(5,819)	(51,659)
Dividends paid	(56,861)	(45,265)	(43,302)
Net cash (used in) provided by financing activities	811,488	2,565,910	935,060
Cash and cash equivalents at beginning of year	1,813,987
Cash and cash equivalents at end of year	2,608,444	1,813,987
Parent
Cash flows from operating activities:
Net income	224,750	201,209	192,736
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in undistributed net income of subsidiaries	(113,196)	(150,290)	(134,305)
Amortization of discount and origination costs on borrowings	894	720	633
Stock based compensation expense	10,691	8,450	7,808
Excess tax (benefit) expense on restricted stock vested	(691)	243	21
Deferred tax expense (benefit)	(210)	96	2,165
Net change in other assets	1,020	(590)	1,863
Net change in other liabilities	500	(952)	(64)
Net cash provided by operating activities	123,758	58,886	70,857
Cash flows from investing activities:
Capital investment in subsidiaries	0	(120,000)	0
Cash acquired in connection with acquisition	0	0	339
Cash paid in connection with acquisition	0	0	(9)
Net cash (used in) provided by investing activities	0	(120,000)	330
Cash flows from financing activities:
Proceeds from other borrowings	75,000	148,653	65,000
Repayments of other borrowings	(104,500)	(39,250)	(40,500)
Offering costs paid in connection with acquired bank	0	0	(804)
Repurchase of common stock	(32,132)	(5,819)	(51,659)
Dividends paid	(56,861)	(45,265)	(43,302)
Net cash (used in) provided by financing activities	(118,493)	58,319	(71,265)
Net change in cash and cash equivalents	5,265	(2,795)	(78)
Cash and cash equivalents at beginning of year	5,482	8,277	8,355
Cash and cash equivalents at end of year	$ 10,747	$ 5,482	$ 8,277

Subsequent Events - Narrative (

Subsequent Events - Narrative (Details) - Subsequent event - USD ($)	Feb. 25, 2022	Feb. 17, 2022	Feb. 16, 2022	Jan. 28, 2022
Subsequent Event [Line Items]
Dividends declared (in usd per share)				$ 0.38
Dividends paid		$ 16,238,000
Revolving line of credit | Line of Credit
Subsequent Event [Line Items]
Line of credit, maximum capacity			$ 100,000,000
Borrowings against line of credit	$ 0
Revolving line of credit | Line of Credit | Bloomberg Short-Term Bank Yield Index (BSBY)
Subsequent Event [Line Items]
Basis spread on variable rate			1.75%