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REGULATORY MATTERS - Narrative (Details) - USD ($) | Mar. 31, 2021 | Dec. 31, 2019
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Subordinated debentures | Subordinated Debentures II, Subordinated Debentures III, and DCB Debentures I |  |
Common equity tier 1 capital to risk-weighted assets: |  |
Debenture issued | $ 10,310,000 | $ 10,310,000
Maximum |  |
Common equity tier 1 capital to risk-weighted assets: |  |
Capital conservation buffer percentage | 2.50% |

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