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Regulatory & Capital Matters (Details) $ in Millions | Dec. 31, 2021 USD ($) | Dec. 31, 2020
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Regulatory & Capital Matters |  |
Tier 1 capital leverage ratio (as a percent) | 7.81 | 10.21
Risk-based capital ratio (as a percent) | 12.55 | 14.26
Phase out of impact of allowance for credit loss | $ 3.8 |
Deferment of impact on retained earnings | $ 3.8 |
Subsidiaries [Member] |  |
Regulatory & Capital Matters |  |
Tier 1 capital leverage ratio (as a percent) | 9.58 | 10.74
Risk-based capital ratio (as a percent) | 13.46 | 15.00
Minimum | Subsidiaries [Member] |  |
Regulatory & Capital Matters |  |
Tier 1 capital leverage ratio (as a percent) | 8 |
Risk-based capital ratio (as a percent) | 12 |

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- Definition Ratio of total risk-based capital to risk-weighted assets as defined by regulatory framework. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 + Details
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