Derivative Financial Instruments - Schedule of Derivative Financial Instruments on Statements of Income (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Derivative [Line Items]
Derivatives in hedging relationships	$ 9,392	$ 21,293	$ 22,713
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest Income (Expense), after Provision for Loan Loss
Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivatives in hedging relationships	$ 9,716	20,940	23,691
Designated as Hedging Instrument [Member] \| Interest on long-term borrowings [Member] \| Interest Rate Contracts [Member] \| Cash Flow Hedging [Member]
Derivative [Line Items]
Derivatives in hedging relationships	9,718	20,932	23,574
Designated as Hedging Instrument [Member] \| Interest And Fees On Loans And Leases [Member] \| Interest Rate Contracts [Member] \| Fair Value Hedging [Member]
Derivative [Line Items]
Derivatives in hedging relationships	(2)	8	117
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivatives not designated as hedging instruments	(324)	353	(978)
Not Designated as Hedging Instrument [Member] \| Income from Mortgage Banking Activities [Member] \| TBA Mortgage Backed Securities [Member]
Derivative [Line Items]
Derivatives not designated as hedging instruments	(348)	956	(611)
Not Designated as Hedging Instrument [Member] \| Income from Mortgage Banking Activities [Member] \| Interest Rate Lock Commitments [Member]
Derivative [Line Items]
Derivatives not designated as hedging instruments	(11)	(489)	(240)
Not Designated as Hedging Instrument [Member] \| Income from Mortgage Banking Activities [Member] \| Forward Loan Sale Commitments [Member]
Derivative [Line Items]
Derivatives not designated as hedging instruments	$ 35	$ (114)	$ (127)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
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-Name Accounting Standards Codification
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