Regulatory Matters (Details) $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Maximum Subsidiary Dividend	$ 73,600
Arrow
Actual, Amount
Total Capital (to Risk Weighted Assets)	447,091	$ 435,857
Tier I Capital (to Risk Weighted Assets)	414,221	404,059
Tier One Capital (to Average Assets)	414,221	404,059
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 394,166	$ 384,003
Actual, Ratio
Total Capital (to Risk Weighted Assets)	0.147	0.151
Tier I Capital (to Risk Weighted Assets)	0.137	0.140
Tier One Leverage Capital (to Average Assets)	0.098	0.098
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.130	0.133
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)	$ 319,351	$ 303,079
Tier I Capital (to Risk Weighted Assets)	256,998	245,322
Tier One Leverage Capital (to Average Assets)	169,070	164,922
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 212,243	$ 202,107
Minimum Amounts For Capital Adequacy Purposes, Ratio
Total Capital (to Risk Weighted Assets)	0.105	0.105
Tier I Capital (to Risk Weighted Assets)	0.085	0.085
Tier One Leverage Capital (to Average Assets)	0.040	0.040
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.070	0.070
Minimum Amounts To Be Well-Capitalized, Amount
Total Capital (to Risk Weighted Assets)	$ 304,144	$ 288,647
Tier I Capital (to Risk Weighted Assets)	241,881	230,891
Tier One Leverage Capital (to Average Assets)	211,337	206,153
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)	$ 197,083	$ 187,671
Minimum Amounts To Be Well-Capitalized
Total Capital (to Risk Weighted Assets)	0.100	0.100
Tier One Risk Based Capital (to Risk Weighted Assets)	0.080	0.080
Tier One Leverage Capital (to Average Assets)	0.050	0.050
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.065	0.065
Glens Falls National
Actual, Amount
Total Capital (to Risk Weighted Assets)	$ 320,449	$ 315,458
Tier I Capital (to Risk Weighted Assets)	297,667	292,134
Tier One Capital (to Average Assets)	297,667	292,134
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 297,612	$ 292,078
Actual, Ratio
Total Capital (to Risk Weighted Assets)	0.143	0.143
Tier I Capital (to Risk Weighted Assets)	0.132	0.132
Tier One Leverage Capital (to Average Assets)	0.092	0.090
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.132	0.132
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)	$ 235,295	$ 231,630
Tier I Capital (to Risk Weighted Assets)	191,680	188,117
Tier One Leverage Capital (to Average Assets)	129,420	129,837
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 157,825	$ 154,890
Minimum Amounts For Capital Adequacy Purposes, Ratio
Total Capital (to Risk Weighted Assets)	0.105	0.105
Tier I Capital (to Risk Weighted Assets)	0.085	0.085
Tier One Leverage Capital (to Average Assets)	0.040	0.040
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.070	0.070
Minimum Amounts To Be Well-Capitalized, Amount
Total Capital (to Risk Weighted Assets)	$ 224,090	$ 220,600
Tier I Capital (to Risk Weighted Assets)	180,404	177,051
Tier One Leverage Capital (to Average Assets)	161,776	162,297
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)	$ 146,551	$ 143,826
Minimum Amounts To Be Well-Capitalized
Total Capital (to Risk Weighted Assets)	0.100	0.100
Tier One Risk Based Capital (to Risk Weighted Assets)	0.080	0.080
Tier One Leverage Capital (to Average Assets)	0.050	0.050
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.065	0.065
Saratoga National
Actual, Amount
Total Capital (to Risk Weighted Assets)	$ 110,510	$ 104,279
Tier I Capital (to Risk Weighted Assets)	100,449	95,891
Tier One Capital (to Average Assets)	100,449	95,891
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 100,449	$ 95,891
Actual, Ratio
Total Capital (to Risk Weighted Assets)	0.137	0.155
Tier I Capital (to Risk Weighted Assets)	0.125	0.143
Tier One Leverage Capital (to Average Assets)	0.096	0.105
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.125	0.143
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)	$ 84,697	$ 70,641
Tier I Capital (to Risk Weighted Assets)	68,305	56,998
Tier One Leverage Capital (to Average Assets)	41,854	36,530
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 56,251	$ 46,940
Minimum Amounts For Capital Adequacy Purposes, Ratio
Total Capital (to Risk Weighted Assets)	0.105	0.105
Tier I Capital (to Risk Weighted Assets)	0.085	0.085
Tier One Leverage Capital (to Average Assets)	0.040	0.040
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.070	0.070
Minimum Amounts To Be Well-Capitalized, Amount
Total Capital (to Risk Weighted Assets)	$ 80,664	$ 67,277
Tier I Capital (to Risk Weighted Assets)	64,287	53,645
Tier One Leverage Capital (to Average Assets)	52,317	45,662
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)	$ 52,233	$ 43,587
Minimum Amounts To Be Well-Capitalized
Total Capital (to Risk Weighted Assets)	0.100	0.100
Tier One Risk Based Capital (to Risk Weighted Assets)	0.080	0.080
Tier One Leverage Capital (to Average Assets)	0.050	0.050
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.065	0.065

Banking Regulation, Risk-Based Information, Capital Required for Capital Adequacy

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Tier One Risk Based Capital Required For Capital Adequacy, With Buffer

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Ratio of minimum Common Equity Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
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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.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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