SHAREHOLDERS' EQUITY AND EARNINGS PER COMMON SHARE - Actual and Required Capital Ratios (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Actual
Total capital to risk-weighted assets	$ 353,239	$ 341,492
Common equity tier 1 capital to risk-weighted assets	273,178	265,205
Tier 1 capital to risk-weighted assets	273,178	285,825
Tier 1 capital to average assets	$ 273,178	$ 285,825
Total capital to risk-weighted assets, ratio	13.56	13.61
Common equity tier 1 capital to risk-weighted assets, ratio	10.49	10.57
Tier 1 capital to risk-weighted assets, ratio	11.28	11.39
Tier 1 capital to average assets, ratio	8.12	8.13
Capital Required For Capital Adequacy [Abstract]
Total capital to risk-weighted assets	$ 273,479	$ 263,377
Common equity tier 1 capital to risk-weighted assets	182,320	175,584
Tier 1 capital to risk-weighted assets	205,850	213,211
Tier 1 capital to average assets	$ 168,147	$ 175,890
Regulatory minimum to be well capitalized, Total capital to risk-weighted assets, ratio	10.50	10.50
Regulatory minimum to be well capitalized, Common equity tier 1 capital to risk-weighted assets, ratio	7.00%	7.00%
Regulatory minimum to be well capitalized, Tier 1 capital to risk-weighted assets, ratio	8.50	8.50
Regulatory minimum to be well capitalized, Tier 1 capital to average assets, ratio	5.00	5.00
Bank
Actual
Total capital to risk-weighted assets	$ 345,397	$ 310,982
Common equity tier 1 capital to risk-weighted assets	325,956	295,315
Tier 1 capital to risk-weighted assets	325,956	295,315
Tier 1 capital to average assets	$ 325,956	$ 295,315
Total capital to risk-weighted assets, ratio	13.27	12.42
Common equity tier 1 capital to risk-weighted assets, ratio	12.52	11.79
Tier 1 capital to risk-weighted assets, ratio	12.52	11.79
Tier 1 capital to average assets, ratio	9.02	8.39
Capital Required For Capital Adequacy [Abstract]
Total capital to risk-weighted assets	$ 273,298	$ 262,999
Common equity tier 1 capital to risk-weighted assets	182,244	175,332
Tier 1 capital to risk-weighted assets	221,296	212,904
Tier 1 capital to average assets	$ 180,685	$ 175,996
Regulatory minimum to be well capitalized, Total capital to risk-weighted assets, ratio	10.50	10.50
Regulatory minimum to be well capitalized, Common equity tier 1 capital to risk-weighted assets, ratio	7.00%	7.00%
Regulatory minimum to be well capitalized, Tier 1 capital to risk-weighted assets, ratio	8.50	8.50
Regulatory minimum to be well capitalized, Tier 1 capital to average assets, ratio	5.00	5.00

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