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v3.20.4

Regulatory Capital Requirements (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Tier I Capital (to average assets) [Abstract] |  |
Tier I capital to average assets | $ 1,018,320 | $ 963,147
Tier I capital to average assets ratio | 0.0956 | 0.1033
Minimum Tier I leverage capital required for capital adequacy to average assets | 0.0400 | 0.0400
Tier I leverage capital required for classification as well capitalized to average assets | 0.0500 | 0.0500
Common Equity Tier I Capital [Abstract] |  |
Common equity Tier I capital | $ 921,320 | $ 866,147
Common equity Tier I capital ratio | 0.1184 | 0.1129
Minimum Tier I capital required for capital adequacy | 0.0450 | 0.0450
Minimum Tier I capital required for capital adequacy plus buffer | 0.0700 | 0.0700
Tier I capital required for classification as well capitalized | 0.0650 | 0.0650
Tier I Capital (to risk weighted assets) [Abstract] |  |
Tier I capital to risk weighted assets | $ 1,018,320 | $ 963,147
Tier I capital to risk weighted assets ratio | 0.1309 | 0.1256
Minimum Tier I capital required for capital adequacy to risk weighted assets | 0.0600 | 0.0600
Minimum Tier I capital required for capital adequacy plus buffer to risk weighted assets | 0.0850 | 0.0850
Tier I capital required for classification as well capitalized to risk weighted assets | 0.0800 | 0.0800
Total Capital (to risk weighted assets) [Abstract] |  |
Total capital to risk weighted assets | $ 1,215,672 | $ 1,037,041
Total capital to risk weighted assets ratio | 0.1562 | 0.1352
Minimum capital required for capital adequacy to risk weighted assets | 0.0800 | 0.0800
Total capital required for capital adequacy plus buffer to average assets | 0.1050 | 0.1050
Capital required for classification as well capitalized to risk weighted assets | 0.1000 | 0.1000
Permissible capital transition relief period | 5 years |
NBT Bank [Member] |  |
Tier I Capital (to average assets) [Abstract] |  |
Tier I capital to average assets | $ 1,054,097 | $ 894,407
Tier I capital to average assets ratio | 0.0995 | 0.0964
Minimum Tier I leverage capital required for capital adequacy to average assets | 0.0400 | 0.0400
Tier I leverage capital required for classification as well capitalized to average assets | 0.0500 | 0.0500
Common Equity Tier I Capital [Abstract] |  |
Common equity Tier I capital | $ 1,054,097 | $ 894,407
Common equity Tier I capital ratio | 0.1367 | 0.1176
Minimum Tier I capital required for capital adequacy | 0.0450 | 0.0450
Minimum Tier I capital required for capital adequacy plus buffer | 0.0700 | 0.0700
Tier I capital required for classification as well capitalized | 0.0650 | 0.0650
Tier I Capital (to risk weighted assets) [Abstract] |  |
Tier I capital to risk weighted assets | $ 1,054,097 | $ 894,407
Tier I capital to risk weighted assets ratio | 0.1367 | 0.1176
Minimum Tier I capital required for capital adequacy to risk weighted assets | 0.0600 | 0.0600
Minimum Tier I capital required for capital adequacy plus buffer to risk weighted assets | 0.0850 | 0.0850
Tier I capital required for classification as well capitalized to risk weighted assets | 0.0800 | 0.0800
Total Capital (to risk weighted assets) [Abstract] |  |
Total capital to risk weighted assets | $ 1,150,544 | $ 968,301
Total capital to risk weighted assets ratio | 0.1493 | 0.1273
Minimum capital required for capital adequacy to risk weighted assets | 0.0800 | 0.0800
Total capital required for capital adequacy plus buffer to average assets | 0.1050 | 0.1050
Capital required for classification as well capitalized to risk weighted assets | 0.1000 | 0.1000

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- Definition The minimum Common Equity Tier 1 Capital ratio (Common Equity Tier 1 Capital divided by Risk-based Assets) required for capital adequacy plus buffer purposes under the regulatory framework for prompt corrective action. + References No definition available. + Details
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