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Shareholder's Equity - Summary of Actual Capital Amount and Well Capitalized Total Risk-Based, Tier I Risk-Based, and Tier I Leverage Ratios (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
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Equity [Abstract] |  |
Common equity Tier 1 capital (to risk-weighted assets), Actual Regulatory Capital, Amount | $ 74,375 | $ 70,177
Tier 1 capital (to risk-weighted assets) Actual Regulatory Capital, Amount | 74,375 | 70,177
Total capital (to risk-weighted assets), Actual Regulatory Capital, Amount | 80,137 | 75,232
Tier 1 capital (to risk-weighted assets), Actual Regulatory Capital, Amount | $ 74,375 | $ 70,177
Common equity Tier 1 capital (to risk-weighted assets), Actual Regulatory Capital, Ratio | 12.78% | 12.62%
Tier 1 capital (to risk-weighted assets), Actual Regulatory Capital, Ratio | 12.78% | 12.62%
Total capital (to risk-weighted assets), Actual Regulatory Capital, Ratio | 13.77% | 13.53%
Tier 1 leverage (to average assets), Actual Regulatory Capital, Ratio | 9.61% | 8.96%
Common equity Tier 1 capital (to risk-weighted assets), Minimum Requirement | 7.00% | 6.375%
Tier 1 capital (to risk-weighted assets), Minimum Requirement | 8.50% | 7.875%
Total capital (to risk-weighted assets), Minimum Requirement | 10.50% | 9.875%
Tier 1 leverage (to average assets), Minimum Requirement | 4.00% | 4.00%
Common equity Tier 1 capital (to risk-weighted assets), To Be Well Capitalized | 6.50% | 6.50%
Tier 1 capital (to risk-weighted assets), To Be Well Capitalized | 8.00% | 8.00%
Total capital (to risk-weighted assets), To Be Well Capitalized | 10.00% | 10.00%
Tier 1 leverage (to average assets), To Be Well Capitalized | 5.00% | 5.00%

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