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Loans And Leases - Additional Information (Details) - USD ($) | 9 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024 | Jun. 30, 2025 | Sep. 30, 2024 | Jun. 30, 2024 | Dec. 31, 2023
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |
Loans and Leases Receivable, Related Parties, Ending Balance | $ 22,900,000 | $ 11,400,000 |  |  |  |
Loans and Leases Receivable, Related Parties, Additions | 11,500,000 | 1,400,000 |  |  |  |
Loans and Leases Receivable, Related Parties, Proceeds | 0 | 1,400,000 |  |  |  |
Decrease to retained earnings | 104,238,000 | 98,624,000 | $ 101,892,000 | $ 98,491,000 | $ 93,836,000 | $ 90,593,000
Minimum commitment required for evaluating idividually |  |  | 500,000 |  |  |
Commitment required for evaluating individually at management discretion |  |  | 500,000 |  |  |
Loans and leases, allowance for credit losses | 10,700,000 | 10,184,000 |  | 10,116,000 |  | 10,507,000
Retained Earnings [Member] |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |
Decrease to retained earnings | 119,520,000 | 116,865,000 | $ 117,988,000 | $ 115,551,000 | $ 113,615,000 | $ 109,959,000
LHFI [Member] |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |
Accrued interest receivable | $ 3,200,000 | $ 2,800,000 |  |  |  |
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Interest Receivable | Interest Receivable |  |  |  |
Allowance for credit loss | $ 0 | $ 0 |  |  |  |
Reserve for Unfunded Commitments [Member] |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |
Loans and leases, allowance for credit losses | $ 400,000 | $ 400,000 |  |  |  |
Real Estate [Member] |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |
Percentage of Loan Portfolio | 49.60% | 56.40% |  |  |  |
Pledged as Collateral [Member] | FHLB Borrowings [Member] |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |
Loans pledged as collateral | $ 86,500,000 | $ 92,600,000 |  |  |  |
Pledged as Collateral [Member] | Federal Reserve Bank Advances [Member] |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |
Loans pledged as collateral | $ 363,900,000 | $ 285,200,000 |  |  |  |

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