Credit Quality - Schedule of Financial Effect of Loan and Lease Modifications (Detail)	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Commercial Real Estate [Member] \| Owner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%	0.00%	0.50%
Weighted Average Payment Delay (in years)	0 years	0 years	1 year	2 years 4 months 24 days
Weighted Average Term Extension (in years)	0 years	0 years	3 years 3 months 18 days	6 months
Commercial Real Estate [Member] \| Nonowner-Occupied [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%	0.00%	0.50%
Weighted Average Payment Delay (in years)	0 years	0 years	0 years	2 years
Weighted Average Term Extension (in years)	0 years	0 years	0 years	4 months 24 days
Other Commercial [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%	0.00%	0.00%
Weighted Average Payment Delay (in years)	2 months 12 days	0 years	2 months 12 days	0 years
Weighted Average Term Extension (in years)	3 months 18 days	0 years	3 months 18 days	1 month 6 days
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%	0.00%	0.00%
Weighted Average Payment Delay (in years)	1 year	0 years	1 year	0 years
Weighted Average Term Extension (in years)	0 years	3 months 18 days	0 years	3 months 18 days
Construction & Land Development [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%	0.00%	0.00%
Weighted Average Payment Delay (in years)	0 years	0 years	0 years	0 years
Weighted Average Term Extension (in years)	0 years	0 years	0 years	0 years
Consumer [Member] \| Bankcard [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%	0.00%	0.00%
Weighted Average Payment Delay (in years)	0 years	0 years	0 years	0 years
Weighted Average Term Extension (in years)	0 years	0 years	0 years	0 years
Consumer [Member] \| Other Consumer [Member]
Financing Receivable, Modifications [Line Items]
Weighted-Average Interest Rate Reduction	0.00%	0.00%	0.00%	0.00%
Weighted Average Payment Delay (in years)	0 years	0 years	0 years	0 years
Weighted Average Term Extension (in years)	0 years	0 years	0 years	0 years

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

No definition available.

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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
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-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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-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

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- Definition

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

+ References

+ Details

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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 reported fact of one year, five months, and thirteen days.

+ References

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