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Basis of Presentation and Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Feb. 28, 2022 | Feb. 15, 2022 | Dec. 31, 2023 | Dec. 31, 2022
Property, Plant and Equipment [Line Items] |  |  |  |
Issuance of common stock |  |  |  | $ 2,446,312
Series A Preferred Stock |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Shares issued for acquisition (in shares) |  | 108,000 |  |
Series C Preferred Stock |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Shares issued for acquisition (in shares) |  | 122,500 |  |
Preferred Stock |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Issuance of common stock | $ 243,700 |  |  |
First Midwest |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Shares issued for acquisition (in shares) | 129,400,000 |  |  |
Issuance of common stock | $ 2,400,000 |  |  |
Minimum |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Maturity of short-term securities sold under agreements to repurchase |  |  | 1 day |
Minimum | Core Deposits and Other Intangible Assets |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Estimated useful lives of core deposits and customer relationships |  |  | 5 years |
Minimum | Building and Building Improvements |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Useful lives for premises and equipment, years |  |  | 10 years |
Minimum | Furniture and Equipment |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Useful lives for premises and equipment, years |  |  | 3 years |
Maximum |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Maturity of short-term securities sold under agreements to repurchase |  |  | 4 days |
Maximum | Core Deposits and Other Intangible Assets |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Estimated useful lives of core deposits and customer relationships |  |  | 15 years |
Maximum | Building and Building Improvements |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Useful lives for premises and equipment, years |  |  | 39 years |
Maximum | Furniture and Equipment |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |
Useful lives for premises and equipment, years |  |  | 7 years |

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