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Summary of Significant Accounting Policies (Details) |  | 12 Months Ended
--- | --- | ---
Oct. 01, 2021 USD ($) | Dec. 31, 2023 USD ($) item | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Summary of Significant Accounting Policies |  |  |  |
Number of insurance-related subsidiaries | item |  | 1 |  |
Investment Securities |  |  |  |
Number of components in which other-than-temporary impairment is segregated | item |  | 2 |  |
Non-Accrual Loans |  |  |  |
Period of charge off for past due unsecured consumer loans |  | 90 days |  |
Minimum period that past due unsecured loans outstanding may not be placed on nonaccrual status under special circumstances |  | 90 days |  |
Maximum period of non-consumer loans outstanding that is used to evaluate whether loans should be placed on non-accrual status |  | 90 days |  |
Other Real Estate Owned and Repossessed Assets |  |  |  |
Other real estate owned |  | $ 26,728,000 | $ 30,144,000 |
Repossessed assets |  | $ 236,000 | 4,637,000 |
Income Taxes |  |  |  |
Percentage of likelihood of realization of recognized tax benefit |  | 50.00% |  |
Liability for unrecognized tax benefits |  | $ 0 | 0 |
Interest expense related to uncertain tax positions |  | 0 | 0 | $ 0
Penalties related to uncertain tax positions |  | 0 | 0 | $ 0
Goodwill and Identified Intangible Assets |  |  |  |
Goodwill impairment loss | $ 0 |  |  |
Impairment of identified intangible assets |  | $ 0 |  |
Segments of an Enterprise and Related Information |  |  |  |
Number of operating segments | item |  | 1 |  |
Number of active operating bank subsidiaries | item |  | 5 |  |
New Accounting Standards |  |  |  |
Retained Earnings (Accumulated Deficit) |  | $ 3,029,088,000 | $ 2,695,567,000 |

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