Regulatory Matters (Details) $ in Thousands	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Maximum subsidiary dividend	$ 44,400
Arrow
Actual, Amount
Total Capital (to Risk Weighted Assets)	452,506	$ 447,091
Tier I Capital (to Risk Weighted Assets)	417,338	414,221
Tier One Capital (to Average Assets)	417,338	414,221
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 397,285	$ 394,166
Actual, Ratio
Total Capital (to Risk Weighted Assets)	0.145	0.147
Tier I Capital (to Risk Weighted Assets)	0.134	0.137
Tier One Leverage Capital (to Average Assets)	0.096	0.098
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.127	0.130
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)	$ 328,268	$ 319,351
Tier I Capital (to Risk Weighted Assets)	265,741	256,998
Tier One Leverage Capital (to Average Assets)	173,952	169,070
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 218,845	$ 212,243
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)	$ 312,636	$ 304,144
Tier I Capital (to Risk Weighted Assets)	250,109	241,881
Tier One Leverage Capital (to Average Assets)	217,440	211,337
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)	$ 203,214	$ 197,083
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
Arrow Bank National Association
Actual, Amount
Total Capital (to Risk Weighted Assets)	$ 435,628
Tier I Capital (to Risk Weighted Assets)	400,460
Tier One Capital (to Average Assets)	400,460
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 400,407
Actual, Ratio
Total Capital (to Risk Weighted Assets)	0.140
Tier I Capital (to Risk Weighted Assets)	0.129
Tier One Leverage Capital (to Average Assets)	0.092
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.129
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)	$ 327,050
Tier I Capital (to Risk Weighted Assets)	264,755
Tier One Leverage Capital (to Average Assets)	173,656
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 218,033
Minimum Amounts For Capital Adequacy Purposes, Ratio
Total Capital (to Risk Weighted Assets)	0.105
Tier I Capital (to Risk Weighted Assets)	0.085
Tier One Leverage Capital (to Average Assets)	0.040
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.070
Minimum Amounts To Be Well-Capitalized, Amount
Total Capital (to Risk Weighted Assets)	$ 311,476
Tier I Capital (to Risk Weighted Assets)	249,181
Tier One Leverage Capital (to Average Assets)	217,070
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)	$ 202,459
Minimum Amounts To Be Well-Capitalized
Total Capital (to Risk Weighted Assets)	0.100
Tier One Risk Based Capital (to Risk Weighted Assets)	0.080
Tier One Leverage Capital (to Average Assets)	0.050
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.065
Glens Falls National
Actual, Amount
Total Capital (to Risk Weighted Assets)		$ 320,449
Tier I Capital (to Risk Weighted Assets)		297,667
Tier One Capital (to Average Assets)		297,667
Common Equity Tier 1 Capital (to Risk Weighted Assets)		$ 297,612
Actual, Ratio
Total Capital (to Risk Weighted Assets)		0.143
Tier I Capital (to Risk Weighted Assets)		0.132
Tier One Leverage Capital (to Average Assets)		0.092
Common Equity Tier 1 Capital (to Risk Weighted Assets)		0.132
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)		$ 235,295
Tier I Capital (to Risk Weighted Assets)		191,680
Tier One Leverage Capital (to Average Assets)		129,420
Common Equity Tier 1 Capital (to Risk Weighted Assets)		$ 157,825
Minimum Amounts For Capital Adequacy Purposes, Ratio
Total Capital (to Risk Weighted Assets)		0.105
Tier I Capital (to Risk Weighted Assets)		0.085
Tier One Leverage Capital (to Average Assets)		0.040
Common Equity Tier 1 Capital (to Risk Weighted Assets)		0.070
Minimum Amounts To Be Well-Capitalized, Amount
Total Capital (to Risk Weighted Assets)		$ 224,090
Tier I Capital (to Risk Weighted Assets)		180,404
Tier One Leverage Capital (to Average Assets)		161,776
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)		$ 146,551
Minimum Amounts To Be Well-Capitalized
Total Capital (to Risk Weighted Assets)		0.100
Tier One Risk Based Capital (to Risk Weighted Assets)		0.080
Tier One Leverage Capital (to Average Assets)		0.050
Common Equity Tier 1 Capital (to Risk Weighted Assets)		0.065
Saratoga National
Actual, Amount
Total Capital (to Risk Weighted Assets)		$ 110,510
Tier I Capital (to Risk Weighted Assets)		100,449
Tier One Capital (to Average Assets)		100,449
Common Equity Tier 1 Capital (to Risk Weighted Assets)		$ 100,449
Actual, Ratio
Total Capital (to Risk Weighted Assets)		0.137
Tier I Capital (to Risk Weighted Assets)		0.125
Tier One Leverage Capital (to Average Assets)		0.096
Common Equity Tier 1 Capital (to Risk Weighted Assets)		0.125
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)		$ 84,697
Tier I Capital (to Risk Weighted Assets)		68,305
Tier One Leverage Capital (to Average Assets)		41,854
Common Equity Tier 1 Capital (to Risk Weighted Assets)		$ 56,251
Minimum Amounts For Capital Adequacy Purposes, Ratio
Total Capital (to Risk Weighted Assets)		0.105
Tier I Capital (to Risk Weighted Assets)		0.085
Tier One Leverage Capital (to Average Assets)		0.040
Common Equity Tier 1 Capital (to Risk Weighted Assets)		0.070
Minimum Amounts To Be Well-Capitalized, Amount
Total Capital (to Risk Weighted Assets)		$ 80,664
Tier I Capital (to Risk Weighted Assets)		64,287
Tier One Leverage Capital (to Average Assets)		52,317
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)		$ 52,233
Minimum Amounts To Be Well-Capitalized
Total Capital (to Risk Weighted Assets)		0.100
Tier One Risk Based Capital (to Risk Weighted Assets)		0.080
Tier One Leverage Capital (to Average Assets)		0.050
Common Equity Tier 1 Capital (to Risk Weighted Assets)		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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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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