Concentration of loans in a single industry in excess of ten percent

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- Definition

Maximum Percentage of Loan Related To Single Industry

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- Definition

Percentage of total energy loans to total loans excluding PPP Loans

+ References

No definition available.

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Percentage of total energy loans to total loans

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No definition available.

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- Definition

Texas Leading Index economic condition indicator

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No definition available.

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- Definition

U.S. dollar denominated loans and commitments to borrowers in Mexico

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No definition available.

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- Definition

Unfunded balances

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No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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Loans - Additional Information (Detail) $ in Thousands	3 Months Ended
Loans - Additional Information (Detail) $ in Thousands	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration of loans in a single industry in excess of ten percent	0.00%
Maximum percentage loan related to single industry	10.00%
U.S. dollar denominated loans and commitments to borrowers in Mexico	$ 0		$ 0
Loans and Leases Receivable, Related Parties	346,500		$ 350,500
Loans modified as troubled debt restructurings	$ 0	$ 0
Texas Leading Index economic condition indicator	141.2		135.9
Financing Receivable, Allowance for Credit Loss	$ 246,835		$ 248,666
Commercial and Industrial Total Energy Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of total energy loans to total loans	6.30%
Percentage of total energy loans to total loans excluding PPP Loans	6.30%
Financing Receivable, Allowance for Credit Loss	$ 15,422	33,472	17,217	$ 39,553
Paycheck Protection Program [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss	0	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	407	$ 453
Commitments to Extend Credit [Member] \| Commercial and Industrial Total Energy Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unfunded balances	862,200
Standby Letters of Credit [Member] \| Commercial and Industrial Total Energy Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unfunded balances	76,000
Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	$ 39,500		$ 40,000