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Number of banking locations.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Recent Developments, Including Mergers and Acquisitions - Additional Information (Detail) $ in Thousands				3 Months Ended
	Feb. 08, 2022 USD ($) Location	Jun. 17, 2021 USD ($)	May 20, 2021 USD ($) Location	Mar. 31, 2021 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Jan. 22, 2021 USD ($)
Business Combination Separately Recognized Transactions [Line Items]
Total assets					$ 12,530,073	$ 9,405,612
Loans held for investment (net of unearned interest)					6,613,283	6,169,442
Deposits					11,142,688	8,091,914
Goodwill					$ 183,639	$ 149,922
First National Bank and Trust [Member]
Business Combination Separately Recognized Transactions [Line Items]
Purchase price			$ 21,000
Total assets			284,000
Loans held for investment (net of unearned interest)			195,000
Deposits			256,000
Bargain purchase gain			4,800
Purchase expenses			4,800
Intangibles assets, net			$ 1,700
Subordinated Notes due 2036 [Member] \| Private Placement [Member]
Business Combination Separately Recognized Transactions [Line Items]
Aggregate principal amount		$ 60,000
Fixed-to-floating rate		3.50%
Debt instrument maturity year		2036
Oklahoma [Member]
Business Combination Separately Recognized Transactions [Line Items]
Sale of Loans							$ 21,000
Deposits sold							$ 38,000
Oklahoma [Member] \| Noninterest Income [Member]
Business Combination Separately Recognized Transactions [Line Items]
Gain on transaction				$ 2,500
Oklahoma [Member] \| First National Bank and Trust [Member]
Business Combination Separately Recognized Transactions [Line Items]
Number of banking locations \| Location			2
Worthington [Member]
Business Combination Separately Recognized Transactions [Line Items]
Purchase price	$ 77,700
Total assets	478,000
Loans held for investment (net of unearned interest)	257,000
Deposits	430,000
Intangibles assets, net	5,900
Goodwill	$ 33,700
Worthington [Member] \| Arlington, Texas [Member]
Business Combination Separately Recognized Transactions [Line Items]
Number of banking locations \| Location	1
Worthington [Member] \| Colleyville, Texas [Member]
Business Combination Separately Recognized Transactions [Line Items]
Number of banking locations \| Location	1
Worthington [Member] \| Fort Worth, Texas [Member]
Business Combination Separately Recognized Transactions [Line Items]
Number of banking locations \| Location	2