Subsequent Event (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Dec. 31, 2024
Subsequent Event [Line Items]
Total Loans	$ 3,416,868	$ 3,394,541
Commercial Real Estate
Subsequent Event [Line Items]
Total Loans	804,015	796,365
Commercial Real Estate \| Real Estate Loan, Participation
Subsequent Event [Line Items]
Allowance increase (decrease), specific reserve	(3,750)
Total Loans	$ 15,000
Participation percentage	22.00%
Commercial Real Estate \| Real Estate Loan, Participation \| Multiple Banks
Subsequent Event [Line Items]
Total Loans	$ 67,000	$ 86,100

Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Period Increase (Decrease), Reserve

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Financing Receivable, Excluding Accrued Interest, Participation Percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	arow_
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Period Type:	instant

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

+ Details

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Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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- Details

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