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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- Definition

Unfunded balances

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- Definition

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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- Definition

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

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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) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
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%
Loans and Leases Receivable, Related Parties	$ 289,700		$ 289,700			$ 353,100
Texas Leading Index economic condition indicator	131.5		131.5			118.4
Financing Receivable, Allowance for Credit Loss	$ 255,288		$ 255,288			$ 263,177
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	$ 427	$ 570	$ 881	$ 1,600
Commercial and Industrial Total Energy Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of total energy loans to total loans	6.20%		6.20%			7.10%
Percentage of total energy loans to total loans excluding PPP Loans	7.00%		7.00%
Financing Receivable, Allowance for Credit Loss	$ 28,010	$ 40,817	$ 28,010	$ 40,817	$ 33,472	$ 39,553	$ 103,201	$ 37,382
Paycheck Protection Program [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Allowance for Credit Loss	0		0			0
Commitments to Extend Credit [Member] \| Commercial and industrial, Energy [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unfunded balances	930,800		930,800
Standby Letters of Credit [Member] \| Commercial and industrial, Energy [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unfunded balances	60,300		60,300
Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest Receivable	$ 44,600		$ 44,600			$ 48,700