XML 42 R31.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Loans Supplemental Loan Information (Details) - USD ($) $ in Thousands | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2018 | Dec. 31, 2017 | Sep. 30, 2017
Loans and Leases Receivable Disclosure [Abstract] |  |  |
Loans Held-for-sale | $ 201 | $ 327 | $ 1,323
Credit Card Receivable | Consumer Portfolio Segment | Minimum |  |  |
Schedule of Financing Receivable Terms [Line Items] |  |  |
Principal Repayment Terms, Period | 1 year |  |
Credit Card Receivable | Consumer Portfolio Segment | Maximum |  |  |
Schedule of Financing Receivable Terms [Line Items] |  |  |
Principal Repayment Terms, Period | 5 years |  |
Automobile Loan | Consumer Portfolio Segment | Minimum |  |  |
Schedule of Financing Receivable Terms [Line Items] |  |  |
Principal Repayment Terms, Period | 3 years |  |
Automobile Loan | Consumer Portfolio Segment | Maximum |  |  |
Schedule of Financing Receivable Terms [Line Items] |  |  |
Principal Repayment Terms, Period | 7 years |  |

X
- Definition Principal Repayment Terms, Period + References No definition available. + Details
Name: | arow_PrincipalRepaymentTermsPeriod
Namespace Prefix: | arow_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition [Line Items] for Schedule of Financing Receivable Terms [Table] + References No definition available. + Details
Name: | arow_ScheduleofFinancingReceivableTermsLineItems
Namespace Prefix: | arow_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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

X
- Definition Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 + Details
Name: | us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroupMortgage
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CreditCardReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_AutomobileLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |