Financing receivable amount of loans modified.

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Financing receivable impaired interest on nonaccrual loans.

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Loan percentage.

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Nonaccrual loans amount guaranteed by government agencies.

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Percentage of loans secured by real estate.

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Amount of interest income on financing receivable on nonaccrual status.

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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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The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

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Loans Held for Investment and Allowance for Credit Losses on Loans - Additional Information (Detail) - USD ($)	6 Months Ended		12 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Financing Receivable Recorded Investment [Line Items]
Gains (losses) on sale of property held in other real estate owned	$ (79,000)	$ 1,300,000
Interest income recognized on nonaccrual loans	0	0
Interest income that would have been recognized	2,300,000	$ 1,800,000
Balance of modifies loans	3,600,000		$ 14,800,000
Commercial Real Estate
Financing Receivable Recorded Investment [Line Items]
Other real estate	30,700,000		28,100,000
Construction and Development Real Estate Loan
Financing Receivable Recorded Investment [Line Items]
Other real estate	15,600,000
U.S. Federal Agencies [Member]
Financing Receivable Recorded Investment [Line Items]
Nonaccrual loans guaranteed by government agencies	$ 9,500,000		$ 9,000,000
Parent Company [Member]
Financing Receivable Recorded Investment [Line Items]
Percentage of loans secured by real estate	71.00%
BancFirst [Member]
Financing Receivable Recorded Investment [Line Items]
Loan percentage	83.00%
Pegasus and Worthington [Member]
Financing Receivable Recorded Investment [Line Items]
Loan percentage	17.00%