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Recent Developments Including Mergers and Acquisitions - Additional Information (Detail) $ in Thousands | Feb. 08, 2022 USD ($) Location | Jun. 17, 2021 USD ($) | May 20, 2021 USD ($) Location | Jan. 22, 2021 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
--- | --- | --- | --- | --- | --- | --- | ---
Business Combination Separately Recognized Transactions [Line Items] |  |  |  |  |  |  |
Total assets |  |  |  |  | $ 12,387,863 | $ 9,405,612 | $ 9,212,357
Loans held for investment (net of unearned interest) |  |  |  |  | 6,943,563 | 6,169,442 |
Deposits |  |  |  |  | 10,974,228 | 8,091,914 |
Business Combination, Bargain Purchase, Gain, Statement of Income or Comprehensive Income [Extensible Enumeration] |  |  | Noninterest Income, Other |  |  |  |
Goodwill |  |  |  |  | $ 182,055 | $ 149,922 |
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 |  |  |
First National Bank and Trust [Member] |  |  |  |  |  |  |
Business Combination Separately Recognized Transactions [Line Items] |  |  |  |  |  |  |
Total assets |  |  | $ 284,000 |  |  |  |
Loans held for investment (net of unearned interest) |  |  | 195,000 |  |  |  |
Deposits |  |  | 256,000 |  |  |  |
Purchase price |  |  | 21,000 |  |  |  |
Bargain purchase gain |  |  | 4,800 |  |  |  |
Purchase expenses |  |  | 4,800 |  |  |  |
Intangibles assets, net |  |  | $ 1,700 |  |  |  |
First National Bank and Trust [Member] | Oklahoma [Member] |  |  |  |  |  |  |
Business Combination Separately Recognized Transactions [Line Items] |  |  |  |  |  |  |
Number of banking locations | Location |  |  | 2 |  |  |  |
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 |  |  |  |  |
Worthington [Member] |  |  |  |  |  |  |
Business Combination Separately Recognized Transactions [Line Items] |  |  |  |  |  |  |
Total assets | $ 478,000 |  |  |  |  |  |
Loans held for investment (net of unearned interest) | 257,000 |  |  |  |  |  |
Deposits | 430,000 |  |  |  |  |  |
Purchase price | 77,700 |  |  |  |  |  |
Intangibles assets, net | 5,900 |  |  |  |  |  |
Goodwill | $ 32,100 |  |  |  |  |  |
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 |  |  |  |  |  |

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