XML 80 R64.htm IDEA: XBRL DOCUMENT
v3.8.0.1

LOANS AND ALLOWANCE FOR LOAN LOSSES (Summary of Modified Loans Resulting in Troubled Debt Restructurings) (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) Contract | Dec. 31, 2016 USD ($) Contract
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract] |  |
Number of Contracts | Contract | 0 | 1
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 826
Post-Modification Outstanding Recorded Investment | 0 | 832
Recorded Investment at Period End | $ 0 | $ 832

X
- Definition Financing Receivable, Modifications, Subsequent Default, Post-Modification Recorded Investment + References No definition available. + Details
Name: | acnb_FinancingReceivableModificationsSubsequentDefaultPostModificationRecordedInvestment
Namespace Prefix: | acnb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Financing Receivable, Modifications, Subsequent Default, Pre-Modification Recorded Investment + References No definition available. + Details
Name: | acnb_FinancingReceivableModificationsSubsequentDefaultPreModificationRecordedInvestment
Namespace Prefix: | acnb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableGrossAllowanceAndNetAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration