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v3.23.3

Loans - Additional Information (Detail) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2023 USD ($) Rate | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) Rate | Sep. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2021 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Concentration of loans in a single industry in excess of ten percent | 0.00% |  | 0.00% |  |  |  |  |
Maximum percentage loan related to single industry | 10.00% |  | 10.00% |  |  |  |  |
U.S. dollar denominated loans and commitments to borrowers in Mexico | $ 0 |  | $ 0 |  |  | $ 0 |  |
Loans and Leases Receivable, Related Parties | $ 396,700 |  | $ 396,700 |  |  | $ 391,300 |  |
Texas Leading Index economic condition indicator | 129.0 |  | 129.0 |  |  | 130.4 |  |
Financing Receivable, Change in Method, Credit Loss Expense (Reversal) |  |  | $ (45,000) |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | $ 242,235 |  | 242,235 |  |  | $ 227,621 |  |
Loans, net of unearned discounts | $ 18,399,259 |  | $ 18,399,259 |  |  | 17,154,969 |  |
Loans Receivable, Basis Spread on Variable Rate | Rate | 1.75% |  | 1.75% |  |  |  |  |
Loan Receivable Variable Rate | Rate | 10.25% |  | 10.25% |  |  |  |  |
Loan Receivable Fixed Rate | Rate | 6.74% |  | 6.74% |  |  |  |  |
Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | $ 26,586 |  | $ 26,586 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 464 |  | 464 |  |  |  |  |
Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 15,667 |  | 15,667 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 5,341 |  | 5,341 |  |  |  |  |
Payment Deferral |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Loans, net of unearned discounts | 0 | $ 1,083 | 0 | $ 1,083 |  |  |  |
Additional Funding Agreement Terms |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Loans, net of unearned discounts | $ 0 |  | $ 0 |  |  |  |  |
Automobile Loan [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Percentage of total loans | 5.60% |  | 5.60% |  |  |  |  |
Commercial and Industrial Total Energy Loans [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Percentage of total loans | 5.50% |  | 5.50% |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | $ 17,066 | 18,851 | $ 17,066 | 18,851 | $ 14,929 | 18,062 | $ 16,267 | $ 17,217
Financing Receivable, Allowance for Credit Loss, Writeoff | 0 | 0 | 518 | 371 |  |  |  |
Loans, net of unearned discounts | 1,006,859 |  | 1,006,859 |  |  | 925,729 |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 331,902 |  | 331,902 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 72,578 |  | 72,578 |  |  |  |  |
Commercial and Industrial Total Energy Loans [Member] | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 8,148 |  | 8,148 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Commercial and Industrial Total Energy Loans [Member] | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Non Accrual Loans [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Additional interest that would have been recognized on non-accrual loans, net of tax | 1,200 | 372 | 2,700 | 1,200 |  |  |  |
Total consumer real estate loans [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 15,039 | 8,035 | 15,039 | 8,035 | 13,035 | 8,004 | 6,854 | 6,585
Financing Receivable, Allowance for Credit Loss, Writeoff | 170 | 68 | 1,500 | 430 |  |  |  |
Loans, net of unearned discounts | 2,339,363 |  | 2,339,363 |  |  | 1,843,539 |  |
Total consumer real estate loans [Member] | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Total consumer real estate loans [Member] | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Commercial Portfolio Segment [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 74,307 | 98,830 | 74,307 | 98,830 | 75,166 | 104,237 | 87,270 | 72,091
Financing Receivable, Allowance for Credit Loss, Writeoff | 943 | 572 | 14,259 | 5,918 |  |  |  |
Loans, net of unearned discounts | 5,836,877 |  | 5,836,877 |  |  | 5,674,798 |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 1,391,552 |  | 1,391,552 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 877,000 |  | 877,000 |  |  |  |  |
Commercial Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 359 |  | 359 |  |  |  |  |
Commercial Portfolio Segment [Member] | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 124 |  | 124 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 952 |  | 952 |  |  |  |  |
Commercial Portfolio Segment [Member] | Payment Deferral |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Loans, net of unearned discounts | 0 |  | 0 |  |  |  |  |
Consumer Loan [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 9,331 | 7,992 | 9,331 | 7,992 | $ 9,563 | 7,017 | $ 12,135 | $ 7,837
Financing Receivable, Allowance for Credit Loss, Writeoff | 8,189 | 6,549 | 22,147 | 17,642 |  |  |  |
Loans, net of unearned discounts | 459,764 |  | 459,764 |  |  | 492,726 |  |
Consumer Loan [Member] | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 0 |  | 0 |  |  |  |  |
Consumer Loan [Member] | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 15,543 |  | 15,543 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 4,389 |  | 4,389 |  |  |  |  |
Bank Overdrafts | Financial Asset, Other than Financial Asset Acquired with Credit Deterioration | Nonperforming Financial Instruments [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Year One, Originated, Current Fiscal Year | 15,500 |  | 15,500 |  |  |  |  |
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year | 4,200 |  | 4,200 |  |  |  |  |
Paycheck Protection Program [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 0 | $ 0 | 0 | $ 0 |  | 0 |  |
Loans, net of unearned discounts | 17,945 |  | 17,945 |  |  | 34,852 |  |
Commitments to Extend Credit [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financial instruments with off- balance-sheet risk | 12,053,260 |  | 12,053,260 |  |  | 12,137,957 |  |
Commitments to Extend Credit [Member] | Automobile Loan [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Unfunded balances | 459,500 |  | 459,500 |  |  |  |  |
Commitments to Extend Credit [Member] | Commercial and Industrial Total Energy Loans [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Unfunded balances | 1,000,000 |  | 1,000,000 |  |  |  |  |
Standby Letters of Credit [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Financial instruments with off- balance-sheet risk | 370,718 |  | 370,718 |  |  | 383,851 |  |
Standby Letters of Credit [Member] | Automobile Loan [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Unfunded balances | 20,200 |  | 20,200 |  |  |  |  |
Standby Letters of Credit [Member] | Commercial and Industrial Total Energy Loans [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Unfunded balances | 87,200 |  | 87,200 |  |  |  |  |
Loans Receivable [Member] |  |  |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |  |  |
Interest Receivable | $ 83,900 |  | $ 83,900 |  |  | $ 68,700 |  |

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- Definition Percentage added to reference rate used to compute variable rate on loan receivable. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
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- Details
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Balance Type: |
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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