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Regulatory Matters (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Maximum Subsidiary Dividend | $ 44,100 |
Parent Company [Member] |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Total Capital (to Risk Weighted Assets) - Actual Amount | $ 278,163 | $ 258,653
Total Capital (to Risk Weighted Assets) - Actual Ratio | 15.00% | 15.20%
Total Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Amount | $ 172,461 | $ 146,343
Total Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Ratio | 9.30% | 8.60%
Total Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Amount | $ 185,442 | $ 170,166
Total Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Ratio | 10.00% | 10.00%
Tier I Capital (to Risk Weighted Assets) - Actual Amount | $ 259,378 | $ 241,523
Tier I Capital (to Risk Weighted Assets) - Actual Ratio | 14.00% | 14.10%
Tier I Capital (to Risk Weighted Assets) - Minimum Acounts For Capital Adequacy Purposes Amount | $ 135,247 | $ 113,053
Tier I Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Ratio | 7.30% | 6.60%
Tier I Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Ratio | $ 148,216 | $ 137,034
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets | 8.00% | 8.00%
Tier One Risk Based Capital | $ 259,378 | $ 241,523
Tier One Leverage Capital to Average Assets | 9.50% | 9.50%
Tier One Leverage Capital Required for Capital Adequacy | $ 109,212 | $ 101,694
Tier One Leverage Capital Required for Capital Adequacy to Average Assets | 4.00% | 4.00%
Tier One Leverage Capital Required to be Well Capitalized | $ 136,515 | $ 127,117
Tier One Leverage Capital Required to be Well Capitalized to Average Assets | 5.00% | 5.00%
Common Equity Tier 1 Capital Ratio | $ 239,326 | $ 221,472
Common Equity Tier 1 Capital Ratio Percentage | 12.90% | 13.00%
Common Equity Tier 1 Capital Ratio Required for Capital Adequacy | $ 107,604 | $ 86,885
Common Equity Tier 1 Capital Ratio For Capital Adequacy | 5.80% | 5.10%
Common Equity Tier 1 Leverage Capital Required to be Well Capitalized | $ 120,591 | $ 110,736
Common Equity Tier 1 Capital Ratio to be Well Capitalized | 6.50% | 6.50%
Glens Falls National [Member] |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Total Capital (to Risk Weighted Assets) - Actual Amount | $ 220,275 | $ 205,573
Total Capital (to Risk Weighted Assets) - Actual Ratio | 14.60% | 15.00%
Total Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Amount | $ 140,312 | $ 117,862
Total Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Ratio | 9.30% | 8.60%
Total Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Amount | $ 150,873 | $ 137,049
Total Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Ratio | 10.00% | 10.00%
Tier I Capital (to Risk Weighted Assets) - Actual Amount | $ 205,200 | $ 191,679
Tier I Capital (to Risk Weighted Assets) - Actual Ratio | 13.60% | 14.00%
Tier I Capital (to Risk Weighted Assets) - Minimum Acounts For Capital Adequacy Purposes Amount | $ 110,144 | $ 90,363
Tier I Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Ratio | 7.30% | 6.60%
Tier I Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Ratio | $ 120,706 | $ 109,531
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets | 8.00% | 8.00%
Tier One Risk Based Capital | $ 205,200 | $ 191,679
Tier One Leverage Capital to Average Assets | 9.10% | 9.10%
Tier One Leverage Capital Required for Capital Adequacy | $ 90,198 | $ 84,255
Tier One Leverage Capital Required for Capital Adequacy to Average Assets | 4.00% | 4.00%
Tier One Leverage Capital Required to be Well Capitalized | $ 112,747 | $ 105,318
Tier One Leverage Capital Required to be Well Capitalized to Average Assets | 5.00% | 5.00%
Common Equity Tier 1 Capital Ratio | $ 205,148 | $ 191,628
Common Equity Tier 1 Capital Ratio Percentage | 13.60% | 13.90%
Common Equity Tier 1 Capital Ratio Required for Capital Adequacy | $ 87,490 | $ 70,310
Common Equity Tier 1 Capital Ratio For Capital Adequacy | 5.80% | 5.10%
Common Equity Tier 1 Leverage Capital Required to be Well Capitalized | $ 98,049 | $ 89,610
Common Equity Tier 1 Capital Ratio to be Well Capitalized | 6.50% | 6.50%
Saratoga National [Member] |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Total Capital (to Risk Weighted Assets) - Actual Amount | $ 48,822 | $ 42,168
Total Capital (to Risk Weighted Assets) - Actual Ratio | 14.00% | 12.80%
Total Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Amount | $ 32,432 | $ 28,332
Total Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Ratio | 9.30% | 8.60%
Total Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Amount | $ 34,873 | $ 32,944
Total Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Ratio | 10.00% | 10.00%
Tier I Capital (to Risk Weighted Assets) - Actual Amount | $ 45,311 | $ 39,050
Tier I Capital (to Risk Weighted Assets) - Actual Ratio | 13.00% | 11.90%
Tier I Capital (to Risk Weighted Assets) - Minimum Acounts For Capital Adequacy Purposes Amount | $ 25,444 | $ 21,658
Tier I Capital (to Risk Weighted Assets) - Minimum Amounts For Capital Adequacy Purposes Ratio | 7.30% | 6.60%
Tier I Capital (to Risk Weighted Assets) - Minimum Amounts To Be Well-Capitalized Ratio | $ 27,884 | $ 26,252
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets | 8.00% | 8.00%
Tier One Risk Based Capital | $ 45,311 | $ 39,050
Tier One Leverage Capital to Average Assets | 9.40% | 8.90%
Tier One Leverage Capital Required for Capital Adequacy | $ 19,281 | $ 17,551
Tier One Leverage Capital Required for Capital Adequacy to Average Assets | 4.00% | 4.00%
Tier One Leverage Capital Required to be Well Capitalized | $ 24,102 | $ 21,938
Tier One Leverage Capital Required to be Well Capitalized to Average Assets | 5.00% | 5.00%
Common Equity Tier 1 Capital Ratio | $ 45,311 | $ 39,050
Common Equity Tier 1 Capital Ratio Percentage | 13.00% | 11.90%
Common Equity Tier 1 Capital Ratio Required for Capital Adequacy | $ 20,216 | $ 16,736
Common Equity Tier 1 Capital Ratio For Capital Adequacy | 5.80% | 5.10%
Common Equity Tier 1 Leverage Capital Required to be Well Capitalized | $ 22,656 | $ 21,330
Common Equity Tier 1 Capital Ratio to be Well Capitalized | 6.50% | 6.50%

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