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Fair Value of Financial Instruments - Assets Measured at Fair Value on Nonrecurring Basis (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Level 3 [Member] | Collateral Dependent Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | $ 4,646 | $ 2,988
Level 3 [Member] | Loan Servicing Rights [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | 1,982 |
Liability measured at fair value on a nonrecurring basis, Total |  | (4)
Fair Value on Nonrecurring Basis [Member] | Collateral Dependent Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | 4,646 | 2,988
Fair Value on Nonrecurring Basis [Member] | Loan Servicing Rights [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | 1,982 |
Liability measured at fair value on a nonrecurring basis, Total |  | (4)
Fair Value on Nonrecurring Basis [Member] | Level 3 [Member] | Collateral Dependent Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | 4,646 | 2,988
Fair Value on Nonrecurring Basis [Member] | Level 3 [Member] | Loan Servicing Rights [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | $ 1,982 |
Liability measured at fair value on a nonrecurring basis, Total |  | $ (4)

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