Schedule H, Line 4i – Schedule of Assets (Held At End of Year) (Details) - EBP 003	12 Months Ended
Dec. 31, 2025 USD ($)
EBP, Schedule of Asset Held for Investment [Line Items]
Entity Tax Identification Number	22-2448962
EBP, Plan Number	003
Participant Loans	$ 570,540
Total Assets Held for Investment Purposes	$ 45,218,293
Minimum
EBP, Schedule of Asset Held for Investment [Line Items]
Participant loans, interest rate	4.25%
Maximum
EBP, Schedule of Asset Held for Investment [Line Items]
Participant loans, interest rate	9.50%
Investment, Identifier [Axis]: Arrow Financial Corporation \| Employer Common Stock
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	$ 95,295
Investment, Identifier [Axis]: BlackRock Liquidity Funds \| Money Market Fund
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	1,967,829
Investment, Identifier [Axis]: Cash on hand \| Temporary Fund
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	85,705
Investment, Identifier [Axis]: ClearBridge \| International Growth Fund - Class I
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	108,526
Investment, Identifier [Axis]: ClearBridge \| Mid-Cap Fund - Class I
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	57,275
Investment, Identifier [Axis]: Cohen & Steers \| Preferred Securities and Income Fund Inst.
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	403,105
Investment, Identifier [Axis]: Dodge & Cox \| Stock Fund
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	2,092,691
Investment, Identifier [Axis]: FAM Funds \| Small-Cap Fund - Institutional
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	634,765
Investment, Identifier [Axis]: Fidelity Funds \| Balanced Fund
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	6,041,241
Investment, Identifier [Axis]: Fidelity Funds \| Blue Chip Growth
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	6,352,204
Investment, Identifier [Axis]: Fidelity Funds \| Investment Grade Bond Fund
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	1,707,403
Investment, Identifier [Axis]: Goldman Sachs \| Emerging Markets Equity Insights Fund - Inst.
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	204,992
Investment, Identifier [Axis]: Goldman Sachs \| International Equity Insights Fund - Inst.
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	1,898,589
Investment, Identifier [Axis]: Goldman Sachs \| Large-Cap Value Insights Fund - Institutional
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	620,871
Investment, Identifier [Axis]: Goldman Sachs \| US Equity Insights Fund - Institutional
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	14,594
Investment, Identifier [Axis]: Lord Abbett \| Short Duration Inc - R6
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	1,351,344
Investment, Identifier [Axis]: Madison \| Mid Cap Fund - R6
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	1,808,718
Investment, Identifier [Axis]: North Country Funds \| Large-Cap Equity Fund
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	2,161,372
Investment, Identifier [Axis]: Nuveen Funds \| Preferred Securities & Income Fund - Class I
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	68,783
Investment, Identifier [Axis]: PIMCO Funds \| Commodity Real Return Strategy Fund - Inst.
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	81,236
Investment, Identifier [Axis]: Principal Funds \| Small-Cap Fund - Institutional
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	876,336
Investment, Identifier [Axis]: T Rowe Price Funds \| Growth Stock Fund - Class I
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	769,578
Investment, Identifier [Axis]: T Rowe Price Funds \| New Asia Fund - Class I
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	11,811
Investment, Identifier [Axis]: VanEck \| International Investors Gold Fund - Y
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	62,876
Investment, Identifier [Axis]: Vanguard Funds \| 500 Index Admiral
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	7,615,870
Investment, Identifier [Axis]: Vanguard Funds \| Balanced Index - Admiral
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	13,148
Investment, Identifier [Axis]: Vanguard Funds \| Growth Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	429,450
Investment, Identifier [Axis]: Vanguard Funds \| High-Yield Corporate Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	736,043
Investment, Identifier [Axis]: Vanguard Funds \| Mid-Cap Growth Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	339,769
Investment, Identifier [Axis]: Vanguard Funds \| Mid-Cap Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	1,638,248
Investment, Identifier [Axis]: Vanguard Funds \| Mid-Cap Value Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	98,712
Investment, Identifier [Axis]: Vanguard Funds \| Real Estate Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	179,947
Investment, Identifier [Axis]: Vanguard Funds \| Short-Term Bond Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	102,803
Investment, Identifier [Axis]: Vanguard Funds \| Small-Cap Growth Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	93,263
Investment, Identifier [Axis]: Vanguard Funds \| Small-Cap Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	428,369
Investment, Identifier [Axis]: Vanguard Funds \| Small-Cap Value Index - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	31,607
Investment, Identifier [Axis]: Vanguard Funds \| Target Retire 2030
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	311
Investment, Identifier [Axis]: Vanguard Funds \| Target Retire 2035
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	77,960
Investment, Identifier [Axis]: Vanguard Funds \| Target Retire 2040
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	8,119
Investment, Identifier [Axis]: Vanguard Funds \| Target Retire 2045
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	73,074
Investment, Identifier [Axis]: Vanguard Funds \| Target Retire 2050
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	206,068
Investment, Identifier [Axis]: Vanguard Funds \| Target Retire 2055
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	287,674
Investment, Identifier [Axis]: Vanguard Funds \| Target Retire 2060
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	76,630
Investment, Identifier [Axis]: Vanguard Funds \| Target Retire 2065
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	47,632
Investment, Identifier [Axis]: Vanguard Funds \| Total Bond Market Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	2,244,125
Investment, Identifier [Axis]: Vanguard Funds \| Total International St Index - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	90,101
Investment, Identifier [Axis]: Vanguard Funds \| Value Index Fund - Admiral Shares
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	77,559
Investment, Identifier [Axis]: Western Asset Management \| Asset Core Bond Fund - Class IS
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	274,132
Mutual Funds
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	42,498,924
Cash and Money Market Fund
EBP, Schedule of Asset Held for Investment [Line Items]
Current Value	$ 2,053,534

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Exchange Act
-Number 240
-Section 12
-Subsection b-2

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- Definition

Amount of total assets in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, current value of investment, participant loan, and plan interest in master trust.

+ References

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- Definition

Current value of investment, excluding plan interest in master trust, in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract.

+ References

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Balance Type:	debit
Period Type:	instant

- Definition

Amount, after deemed distribution, of participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

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- Definition

Interest rate on participant loan in schedule of asset held for investment of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

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- Definition

Plan number of employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), in three-digit numeric format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule II))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)
-Publisher DOL-EBSA

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule III))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (3)
-Publisher DOL-EBSA

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (4)
-Publisher DOL-EBSA

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 6
-Paragraph d
-Subparagraph (1)
-Publisher DOL-EBSA

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 6
-Paragraph d
-Subparagraph (2)
-Publisher DOL-EBSA

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (2)
-Publisher DOL-EBSA

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(D)
-Publisher DOL-EBSA

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule I))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(A)
-Publisher DOL-EBSA

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(C)
-Publisher DOL-EBSA

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Employee Retirement Income Security Act of 1974
-Number 2520
-Section 103
-Subsection 10
-Paragraph b
-Subparagraph (1)(i)(B)
-Publisher DOL-EBSA

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