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Regulatory Matters (Details) $ in Thousands | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
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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

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