Regulatory Matters (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Maximum Subsidiary Dividend	$ 82,700
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Actual, Amount
Total Capital (to Risk Weighted Assets)	400,661	$ 364,988
Tier I Capital (to Risk Weighted Assets)	371,556	335,756
Tier One Capital (to Average Assets)	371,556	335,756
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 351,497	$ 315,696
Actual, Ratio
Total Capital (to Risk Weighted Assets)	0.157	0.155
Tier I Capital (to Risk Weighted Assets)	0.146	0.142
Tier One Leverage Capital (to Average Assets)	0.092	0.091
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.138	0.134
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)	$ 267,958	$ 247,250
Tier I Capital (to Risk Weighted Assets)	216,317	200,981
Tier One Leverage Capital (to Average Assets)	161,546	147,585
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 178,296	$ 164,916
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)	$ 255,198	$ 235,476
Tier I Capital (to Risk Weighted Assets)	203,592	189,158
Tier One Leverage Capital (to Average Assets)	201,933	184,481
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)	$ 165,560	$ 153,136
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)	$ 295,047	$ 273,801
Tier I Capital (to Risk Weighted Assets)	274,208	251,419
Tier One Capital (to Average Assets)	274,208	251,419
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 274,149	$ 251,359
Actual, Ratio
Total Capital (to Risk Weighted Assets)	0.151	0.152
Tier I Capital (to Risk Weighted Assets)	0.141	0.139
Tier One Leverage Capital (to Average Assets)	0.086	0.087
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.141	0.139
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)	$ 205,165	$ 189,139
Tier I Capital (to Risk Weighted Assets)	165,303	153,745
Tier One Leverage Capital (to Average Assets)	127,539	115,595
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 136,102	$ 126,584
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)	$ 195,395	$ 180,132
Tier I Capital (to Risk Weighted Assets)	155,579	144,702
Tier One Leverage Capital (to Average Assets)	159,423	144,494
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)	$ 126,381	$ 117,542
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)	$ 90,924	$ 78,022
Tier I Capital (to Risk Weighted Assets)	83,432	71,172
Tier One Capital (to Average Assets)	83,432	71,172
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 83,432	$ 71,172
Actual, Ratio
Total Capital (to Risk Weighted Assets)	0.152	0.142
Tier I Capital (to Risk Weighted Assets)	0.139	0.130
Tier One Leverage Capital (to Average Assets)	0.098	0.089
Common Equity Tier 1 Capital (to Risk Weighted Assets)	0.139	0.130
Minimum Amounts For Capital Adequacy, Amount
Total Capital (to Risk Weighted Assets)	$ 62,809	$ 57,692
Tier I Capital (to Risk Weighted Assets)	51,020	46,536
Tier One Leverage Capital (to Average Assets)	34,054	31,987
Common Equity Tier 1 Capital (to Risk Weighted Assets)	$ 42,016	$ 38,323
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)	$ 59,818	$ 54,945
Tier I Capital (to Risk Weighted Assets)	48,018	43,798
Tier One Leverage Capital (to Average Assets)	42,567	39,984
Common Equity Tier 1 Leverage Capital (to Risk Weighted Assets)	$ 39,015	$ 35,586
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