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v3.19.3.a.u2

Risks and Uncertainties - Narrative (Details) | 12 Months Ended
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Dec. 31, 2019 bank subsidiary_business_trusts
Risks and Uncertainties [Abstract] |
Number of banks | bank | 2
Number of business subsidiary trusts | subsidiary_business_trusts | 2

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- Definition Number of Banks + References No definition available. + Details
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- Definition Number of Business Subsidiary Trusts + References No definition available. + Details
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Namespace Prefix: | arow_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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- References No definition available. + Details
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