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Allowance for loans and lease losses write offs net increase (decrease).

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Allowance for loans and lease losses writeoffs net.

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Commitments expected to fund.

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Financing receivable ratio of nonperforming loans to all loans and other real estate.

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Increase decrease in allowance for credit losses percent.

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Loans and lease receivable impaired nonperforming nonaccrual of interest.

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Loans and lease receivable net of deferred income.

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Percentage of loans related to single industry on total loans.

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Percentage of multiple industry loans aggregating to company loan portfolio excluding Warehouse Purchase Program loans.

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Provision for credit losses.

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Provision for loans and lease losses.

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Loans and Allowance for Credit Losses - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Accounts Notes And Loans Receivable [Line Items]
Percentage of Loans Related to Single Industry on Loans	10.00%		10.00%
Percentage of real estate loans aggregating to company loan portfolio, excluding Warehouse Purchase Program loans	80.00%		81.80%
Loans and Leases Receivable, Related Parties	$ 674		$ 272	$ 266
Loans held for investment	$ 23,832,909		$ 20,486,415
Financing Receivable Ratio of Nonperforming Loans to All Loans and Other Real Estate	0.48%		0.69%
Loans and leases receivable, nonaccrual loans	$ 106,500		$ 137,200
Financing Receivable, Allowance for Credit Losses on Loans	$ 383,800		$ 333,700
Allowance for Credit Losses as Percentage of Loans	1.52%		1.53%
Provision for credit losses	$ 0	$ 0
Decrease in allowance for credit losses for loans	$ 50,100
Increase in allowance for credit losses for loans, percentage	15.00%
Net charge-offs	$ 41,309	2,704
Allowance for credit losses on off-balance sheet credit exposures	37,646		$ 37,646
Commitments expected to fund	1,650,000
Nonaccrual loans	106,473		137,217
Revolving Loans	2,394,223
American Bank Holding Corporation [Member]
Accounts Notes And Loans Receivable [Line Items]
Financing Receivable, Allowance for Credit Losses on Loans	47,500
Southwest Bancshares Inc [Member]
Accounts Notes And Loans Receivable [Line Items]
Financing Receivable, Allowance for Credit Losses on Loans	43,900
Troubled Debt Restructuring [Member]
Accounts Notes And Loans Receivable [Line Items]
Allowance for credit losses on off-balance sheet credit exposures	37,600		37,600
PCD Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Net charge-offs	2,000
Revolving Loans	41,675
PCD Loans [Member] \| Merger [Member]
Accounts Notes And Loans Receivable [Line Items]
Revolving Loans	52,100
PCD Loans [Member] \| American Bank Holding Corporation [Member]
Accounts Notes And Loans Receivable [Line Items]
Financing Receivable, Allowance for Credit Losses on Loans	27,500
PCD Loans [Member] \| Southwest Bancshares Inc [Member]
Accounts Notes And Loans Receivable [Line Items]
Financing Receivable, Allowance for Credit Losses on Loans	24,600
PSLs Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Revolving Loans	2,000
PSLs Loans [Member] \| Merger [Member]
Accounts Notes And Loans Receivable [Line Items]
Revolving Loans	39,300
PSLs Loans [Member] \| American Bank Holding Corporation [Member]
Accounts Notes And Loans Receivable [Line Items]
Financing Receivable, Allowance for Credit Losses on Loans	20,000
PSLs Loans [Member] \| Southwest Bancshares Inc [Member]
Accounts Notes And Loans Receivable [Line Items]
Financing Receivable, Allowance for Credit Losses on Loans	19,300
Commercial and Industrial [Member]
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	3,281,253		2,303,936
Provision for credit losses	21,904	(4,996)
Net charge-offs	39,225	$ 330
Increase in net charge-off	33,900
Nonaccrual loans	21,590		61,387
Revolving Loans	1,455,436
Commercial and Industrial [Member] \| PCD Loans [Member]
Accounts Notes And Loans Receivable [Line Items]
Revolving Loans	30,546
Nonperforming Financial Instruments [Member]
Accounts Notes And Loans Receivable [Line Items]
Loans held for investment	$ 122,100		$ 150,800