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Basis of Presentation and Nature of Operations (Details) - bank |  |  | 3 Months Ended
--- | --- | --- | ---
Jan. 11, 2020 | Jul. 01, 2017 | Mar. 31, 2022
Business Acquisition [Line Items] |  |  |
Number of community banking office locations, ACNB |  |  | 31
Adams, Cumberland, Franklin and York Counties, Pennsylvania |  |  |
Business Acquisition [Line Items] |  |  |
Number of community banking office locations, ACNB |  |  | 20
Carroll and Frederick Counties, Maryland |  |  |
Business Acquisition [Line Items] |  |  |
Number of community banking office locations, ACNB |  |  | 11
New Windsor |  |  |
Business Acquisition [Line Items] |  |  |
Number of community banking offices acquired |  | 6 |
Frederick County Bancorp, Inc. |  |  |
Business Acquisition [Line Items] |  |  |
Number of community banking offices acquired | 5 |  |

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- Definition Number of Community Banking Offices, Acquired + References No definition available. + Details
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- Definition Number of Community Banking Offices, Parent + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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