XML 34 R5.htm IDEA: XBRL DOCUMENT
v3.20.1

Consolidated Statements of Income (Parenthetical) | Sep. 27, 2019
--- | ---
Income Statement [Abstract] |
Stock dividend, percent | 3.00%

X
- Definition Stock Dividend, Percent + References No definition available. + Details
Name: | arow_StockDividendPercent
Namespace Prefix: | arow_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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