Credit Quality - Schedule of Financial Effect of Loan and Lease Modifications (Detail)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Commercial Real Estate [Member] \| Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.50%	0.00%
Weighted-Average Other-Than- Insignificant Payment Delay (in years)	2 years 4 months 24 days
Weighted Average Term Extension (in years)	9 months 18 days	3 months 18 days
Commercial Real Estate [Member] \| Nonowner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.50%	0.00%
Weighted-Average Other-Than- Insignificant Payment Delay (in years)	1 year 7 months 6 days
Weighted Average Term Extension (in years)	4 months 24 days	6 months
Other Commercial [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	1.00%
Weighted-Average Other-Than- Insignificant Payment Delay (in years)	0 years
Weighted Average Term Extension (in years)	3 months 18 days	3 months 18 days
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%
Weighted-Average Other-Than- Insignificant Payment Delay (in years)	0 years
Weighted Average Term Extension (in years)	0 years	4 years 10 months 24 days
Construction & Land Development [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%
Weighted-Average Other-Than- Insignificant Payment Delay (in years)	0 years
Weighted Average Term Extension (in years)	0 years	4 years 6 months
Consumer [Member] \| Bankcard [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%
Weighted-Average Other-Than- Insignificant Payment Delay (in years)	0 years
Weighted Average Term Extension (in years)	0 years	0 years
Consumer [Member] \| Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%
Weighted-Average Other-Than- Insignificant Payment Delay (in years)	0 years
Weighted Average Term Extension (in years)	0 years	0 years

Period of payment deferral of financing receivable modified for debtor experiencing financial difficulty.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481933/310-10-55-12A

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-34

Reference 3: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 310
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-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-33

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481962/310-10-50-42

+ Details

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- Definition

Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

+ References

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- Definition

Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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