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Fair Value of Financial Instruments - Quantitative Information about Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements (Detail) $ in Thousands | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
--- | --- | ---
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Fair Value | $ 426,556 | $ 358,478
State and Local Governments [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Fair Value | 64,760 | 67,854
Level 3 [Member] | State and Local Governments [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Fair Value | $ 1,627 | $ 2,460
Valuation Technique | us-gaap:ValuationTechniqueDiscountedCashFlowMember | us-gaap:ValuationTechniqueDiscountedCashFlowMember
Unobservable Inputs | us-gaap:MeasurementInputDiscountRateMember | us-gaap:MeasurementInputDiscountRateMember
Level 3 [Member] | Collateral Dependent Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Fair Value | $ 2,988 | $ 22,676
Valuation Technique | us-gaap:MarketApproachValuationTechniqueMember | us-gaap:MarketApproachValuationTechniqueMember
Unobservable Inputs | us-gaap:MeasurementInputAppraisedValueMember | us-gaap:MeasurementInputAppraisedValueMember
Level 3 [Member] | Loan Servicing Right [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Fair Value |  | $ 58
Valuation Technique |  | us-gaap:ValuationTechniqueDiscountedCashFlowMember
Unobservable Inputs |  | us-gaap:MeasurementInputDiscountRateMember
Fair Value | $ (4) |
Valuation Technique | us-gaap:ValuationTechniqueDiscountedCashFlowMember |
Unobservable Inputs | us-gaap:MeasurementInputDiscountRateMember |
Level 3 [Member] | Minimum [Member] | State and Local Governments [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate | (0.0361) | (0.0017)
Level 3 [Member] | Minimum [Member] | Collateral Dependent Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate | 0.20 | 0
Level 3 [Member] | Minimum [Member] | Loan Servicing Right [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate |  | 0.0511
Discount rate | 0.0936 |
Level 3 [Member] | Maximum [Member] | State and Local Governments [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate | 0.0452 | 0.0492
Level 3 [Member] | Maximum [Member] | Collateral Dependent Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate | 0.30 | 0.50
Level 3 [Member] | Maximum [Member] | Loan Servicing Right [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate |  | 0.228
Discount rate | 6.187 |
Level 3 [Member] | Weighted Average | State and Local Governments [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate | 0.0433 | 0.0349
Level 3 [Member] | Weighted Average | Collateral Dependent Loans [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate | 0.2078 | 0.0041
Level 3 [Member] | Weighted Average | Loan Servicing Right [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Discount rate |  | 0.1087
Discount rate | 1.079 |

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