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v3.23.3

Basis of Presentation and Nature of Operations (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) bank | Sep. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) | Jan. 01, 2023 USD ($) | Dec. 31, 2022 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2021 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Number of community banking office locations, ACNB | bank |  |  | 26 |  |  |  |  |  |
Allowance for credit losses on loans | $ 19,264 | $ 17,952 | $ 19,264 | $ 17,952 | $ 19,148 | $ 17,861 | $ 17,861 | $ 18,943 | $ 19,033
Allowance for unfunded commitments | 1,962 |  | 1,962 |  |  | 92 | 92 |  |
Unfunded Loan Commitment |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Allowance for credit losses on loans | 2,000 |  | 2,000 |  |  |  |  |  |
Provision for Credit Losses | (171) | 0 | 226 | 0 |  |  |  |  |
Financing Receivable Excluding Unfunded Commitments |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Provision for Credit Losses | $ 250 | $ 0 | $ 74 | $ 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 |  |  |
Impact of CECL adoption |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Allowance for credit losses on loans |  |  |  |  |  | 1,600 | $ 1,618 |  |
Impact of CECL adoption | 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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