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Loans and Allowance for Credit Losses - Modifications Subsequent Default (Detail) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024 USD ($) branch	Dec. 31, 2023 USD ($) branch
Financing Receivable, Modified, Subsequent Default [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | branch	3,000	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default | $	$ 259	$ 0
Commercial, financial, agricultural and other [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | branch	2,000	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default | $	$ 164	$ 0
Commercial, financial, agricultural and other [Member] | Equipment Finance
Financing Receivable, Modified, Subsequent Default [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | branch	2,000	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default | $	$ 164	$ 0
Residential real estate [Member]
Financing Receivable, Modified, Subsequent Default [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | branch	1,000	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default | $	$ 95	$ 0
Residential real estate [Member] | Senior Lien
Financing Receivable, Modified, Subsequent Default [Line Items]
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts | branch	1,000	0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default | $	$ 95	$ 0

X

- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

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- Definition

Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

+ References

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