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Regulatory & Capital Matters (Details) $ in Millions | Dec. 31, 2022 USD ($) | Dec. 31, 2021
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Regulatory & Capital Matters |  |
Tier 1 capital leverage ratio (as a percent) | 0.0814 | 0.0781
Risk-based capital ratio (as a percent) | 0.1252 | 0.1255
Phase out of impact of allowance for credit loss | $ 3.8 |
Deferment of impact on retained earnings | $ 2.9 |
Subsidiaries [Member] |  |
Regulatory & Capital Matters |  |
Tier 1 capital leverage ratio (as a percent) | 0.0932 | 0.0958
Risk-based capital ratio (as a percent) | 0.1275 | 0.1346
Minimum | Subsidiaries [Member] |  |
Regulatory & Capital Matters |  |
Tier 1 capital leverage ratio (as a percent) | 0.08 |
Risk-based capital ratio (as a percent) | 0.12 |

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