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Summary of Significant Accounting Policies (Details) $ in Thousands |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 01, 2023 USD ($) board_seat | Dec. 31, 2023 USD ($) segment | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Jan. 01, 2023 USD ($) | Dec. 31, 2020 USD ($)
Basis Of Presentation [Line Items] |  |  |  |  |  |
Settlement of acquired debt |  | $ 31,109 | $ 0 | $ 0 |  |
Restricted cash |  | $ 69,700 | $ 66,800 |  |  |
Loan agreement, repayment performance, reasonable period of time |  | 6 months | 6 months |  |  |
Troubled debt restructurings, extension of the maturity, term |  |  | 1 year |  |  |
Short-term deferrals, term |  |  | 12 months |  |  |
Financing receivable, allowance for credit losses, period beyond a reasonable forecast can be made |  | 2 years |  |  |  |
Financing receivable, allowance for credit losses, historical rates period |  | 1 year |  |  |  |
Number of reportable segments | segment |  | 4 |  |  |  |
LIHTC tax credits and other tax benefits |  | $ 81,600 | $ 37,500 | 27,800 |  |
LIHTC amortization expense |  | $ 63,900 | 30,300 | 20,600 |  |
Award requisite service period |  | 3 years |  |  |  |
Cumulative effect adjustment of Stockholders' equity at adoption |  | $ (5,144,148) | (4,475,801) | (5,296,800) |  | $ (5,161,334)
Retained Earnings |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Cumulative effect adjustment of Stockholders' equity at adoption |  | $ (2,517,226) | (2,234,770) | $ (1,709,980) |  | $ (1,178,019)
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Cumulative effect adjustment of Stockholders' equity at adoption |  |  | 297 |  |  |
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Cumulative effect adjustment of Stockholders' equity at adoption |  |  | 297 |  | $ 297 |
CDI |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Finite-lived intangible asset, useful life |  | 10 years |  |  |  |
Other non-interest expense |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Fair value adjustment on derivative |  | $ 3,900 | $ 6,000 |  |  |
Minimum |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Other intangible assets, useful life |  | 5 years |  |  |  |
Minimum | Buildings and improvements |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 10 years |  |  |  |
Minimum | Furniture, equipment and software |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 3 years |  |  |  |
Minimum | Software and Software Development Costs |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 3 years |  |  |  |
Maximum |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Other intangible assets, useful life |  | 10 years |  |  |  |
Maximum | Buildings and improvements |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 40 years |  |  |  |
Maximum | Furniture, equipment and software |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 10 years |  |  |  |
Maximum | Software and Software Development Costs |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Premises and equipment, useful life |  | 7 years |  |  |  |
Qualpay |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Percentage of business acquired | 60.00% |  |  |  |  |
Number of seats on the Board of Directors acquired | board_seat | 3 |  |  |  |  |
Total number of seats on the Board of Directors of the acquiree | board_seat | 5 |  |  |  |  |
Cash paid | $ 7,000 |  |  |  |  |
Settlement of acquired debt | $ 31,100 |  |  |  |  |
Qualpay | Minimum |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Other intangible assets, useful life |  | 5 years |  |  |  |
Qualpay | Maximum |  |  |  |  |  |
Basis Of Presentation [Line Items] |  |  |  |  |  |
Other intangible assets, useful life |  | 8 years |  |  |  |

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