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Loans And Leases - Additional Information (Details) - USD ($) | 9 Months Ended | 12 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023 | Jun. 30, 2024 | Sep. 30, 2023 | Jun. 30, 2023 | Jan. 01, 2023 | Dec. 31, 2022
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |
Loans and Leases Receivable, Related Parties, Ending Balance | $ 10,700,000 | $ 1,400,000 |  |  |  |  |
Loans and Leases Receivable, Related Parties, Additions | 140,000 | 1,300,000 |  |  |  |  |
Loans and Leases Receivable, Related Parties, Proceeds | 1,400,000 | 0 |  |  |  |  |
Decrease to retained earnings | 98,491,000 | 90,593,000 | $ 93,836,000 | $ 87,408,000 | $ 85,725,000 |  | $ 85,135,000
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 | 10,116,000 | 10,507,000 |  | 11,380,000 |  |  | 9,422,000
Retained Earnings [Member] |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |
Decrease to retained earnings | 115,551,000 | 109,959,000 | $ 113,615,000 | 107,976,000 | $ 106,157,000 |  | $ 104,460,000
Impact of Adopting CECL [Member] |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |
Transition adjustment increase in allowance for credit losses |  |  |  |  |  | $ 2,400,000 |
Decrease to retained earnings |  |  |  | (1,811,000) |  |  |
Loans and leases, allowance for credit losses |  |  |  | 2,123,000 |  |  |
Impact of Adopting CECL [Member] | Retained Earnings [Member] |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |
Decrease to retained earnings |  |  |  | $ (1,811,000) |  | $ (1,800,000) |
Reserve for Unfunded Commitments [Member] |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |
Loans and leases, allowance for credit losses | $ 500,000 | $ 600,000 |  |  |  |  |
Real Estate [Member] |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |
Percentage of Loan Portfolio | 55.80% | 53.60% |  |  |  |  |
Pledged as Collateral [Member] | FHLB Borrowings [Member] |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |
Loans pledged as collateral | $ 93,500,000 | $ 98,600,000 |  |  |  |  |
Pledged as Collateral [Member] | Federal Reserve Bank Advances [Member] |  |  |  |  |  |  |
Debt Securities Heldtomaturity Allowance For Credit Loss [Line Items] |  |  |  |  |  |  |
Loans pledged as collateral | $ 287,500,000 | $ 294,400,000 |  |  |  |  |

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