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v3.23.1

Basis of Presentation and Nature of Operations (Details) $ in Thousands | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2024 | Dec. 31, 2023 | Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 USD ($) bank | Mar. 31, 2022 USD ($) | Jan. 01, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Number of community banking office locations, ACNB | bank |  |  |  |  | 26 |  |  |  |
Allowance for credit losses on loans |  |  |  |  | $ 19,485 | $ 18,963 | $ (17,861) | $ 17,861 | $ 19,033
Allowance for unfunded commitments |  |  |  |  | 2,011 |  | 92 | 92 |
Forecast |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Forecasted Unemployment Rates | 5.10% | 4.70% | 4.30% | 3.90% |  |  |  |  |
Unfunded Loan Commitment |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Allowance for credit losses on loans |  |  |  |  | 2,000 |  |  |  |
Provision for Credit Losses |  |  |  |  | 276 | 0 |  |  |
Financing Receivable Excluding Unfunded Commitments |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Allowance for credit losses on loans |  |  |  |  | 19,500 |  |  |  |
Provision for Credit Losses |  |  |  |  | 97 | $ 0 |  |  |
Revision of Prior Period, Adjustment |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Adjustment |  |  |  |  |  |  | 3,300 |  |
Allowance for credit losses on loans |  |  |  |  |  |  | (1,618) |  |
Allowance for unfunded commitments |  |  |  |  |  |  | $ 1,643 |  |
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Allowance for credit losses on loans |  |  |  |  | 1,600 |  |  | $ 1,618 |
Cumulative Effect, Period of Adoption, Adjustment | Financing Receivable Excluding Unfunded Commitments |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Allowance for credit losses on loans |  |  |  |  | $ (1,600) |  |  |  |
Adams, Cumberland, Franklin and York Counties, Pennsylvania |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Number of community banking office locations, ACNB | bank |  |  |  |  | 17 |  |  |  |
Carroll and Frederick Counties, Maryland |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Number of community banking office locations, ACNB | bank |  |  |  |  | 9 |  |  |  |

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