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Fair Values of Assets and Liabilities - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Other investments | $ 41,458 |  | $ 30,954
Loans Held for Sale | 38,600 |  | 51,991
Other Assets | 10,564 | [1] | 41,569
Total Assets | 1,108,143 |  | 1,241,183
Other Liabilities | 12,835 | [1] | 51,983
Total Liabilities | 12,835 |  | 51,983
Investments, Fair Value Disclosure | 1,058,979 |  | 1,147,623
US Government Agencies Residential Mortgage-backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 2,595 |  | 2,898
US Government Agency Debt Securities Commercial [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 674,907 |  | 724,175
Residential Mortgage Backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 315,046 |  | 350,584
Obligations of U.S. Government-Sponsored Enterprises - Other Government-Sponsored Enterprises [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 976 |  | 946
Obligations of States and Political Subdivisions [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 7,383 |  | 7,527
Corporate Debt Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 58,072 |  | 61,493
Level 1 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Loans Held for Sale | 0 |  | 0
Other Assets | 0 | [1] | 0
Total Assets | 0 |  | 0
Other Liabilities | 0 | [1] | 0
Total Liabilities | 0 |  | 0
Investments, Fair Value Disclosure | 0 |  | 0
Level 1 [Member] | US Government Agencies Residential Mortgage-backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 1 [Member] | US Government Agency Debt Securities Commercial [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 1 [Member] | Residential Mortgage Backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 1 [Member] | Obligations of U.S. Government-Sponsored Enterprises - Other Government-Sponsored Enterprises [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 1 [Member] | Obligations of States and Political Subdivisions [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 1 [Member] | Corporate Debt Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 2 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Loans Held for Sale | 38,600 |  | 51,991
Other Assets | 10,564 | [1] | 41,569
Total Assets | 1,108,143 |  | 1,241,183
Other Liabilities | 12,835 | [1] | 51,983
Total Liabilities | 12,835 |  | 51,983
Investments, Fair Value Disclosure | 1,058,979 |  | 1,147,623
Level 2 [Member] | US Government Agencies Residential Mortgage-backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 2,595 |  | 2,898
Level 2 [Member] | US Government Agency Debt Securities Commercial [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 674,907 |  | 724,175
Level 2 [Member] | Residential Mortgage Backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 315,046 |  | 350,584
Level 2 [Member] | Obligations of U.S. Government-Sponsored Enterprises - Other Government-Sponsored Enterprises [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 976 |  | 946
Level 2 [Member] | Obligations of States and Political Subdivisions [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 7,383 |  | 7,527
Level 2 [Member] | Corporate Debt Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 58,072 |  | 61,493
Level 3 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Loans Held for Sale | 0 |  | 0
Other Assets | 0 | [1] | 0
Total Assets | 0 |  | 0
Other Liabilities | 0 | [1] | 0
Total Liabilities | 0 |  | 0
Investments, Fair Value Disclosure | 0 |  | 0
Level 3 [Member] | US Government Agencies Residential Mortgage-backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 3 [Member] | US Government Agency Debt Securities Commercial [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 3 [Member] | Residential Mortgage Backed Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 3 [Member] | Obligations of U.S. Government-Sponsored Enterprises - Other Government-Sponsored Enterprises [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 3 [Member] | Obligations of States and Political Subdivisions [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | 0 |  | 0
Level 3 [Member] | Corporate Debt Securities [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Investments, Fair Value Disclosure | $ 0 |  | $ 0
[1] | Hedging and non-hedging interest rate derivatives

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