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v3.24.0.1

Merger, Acquisition, and Divestiture Activity - Additional Information (Details) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Nov. 18, 2022 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Oct. 26, 2023 USD ($) $ / shares | Sep. 30, 2023 USD ($) | Dec. 31, 2020 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Allowance for credit losses |  | $ 303,671 | $ 307,610 | $ 303,671 | $ 107,341 |  |  | $ 131,388
Plan assets |  | 16,600 | 0 | 16,600 |  |  |  |
Assets |  | 46,763,372 | 49,089,836 | 46,763,372 |  |  |  |
Total loans |  | 31,123,641 | 32,991,927 | 31,123,641 |  |  |  |
Deposits |  | 35,000,830 | 37,235,180 | 35,000,830 |  |  |  |
Deposits, health savings accounts | $ 382,000 |  |  |  |  |  |  |
Gain on sale of health savings accounts | $ 90,700 |  | 0 | 90,673 | 0 |  |  |
Property optimization |  | 26,800 | 1,559 | 26,818 | $ 0 |  |  |
First Midwest |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Transaction costs, expensed |  |  | 28,700 | 120,900 |  |  |  |
Allowance for credit losses |  | $ 96,300 |  | $ 96,300 |  |  |  |
First Midwest | Unfunded Loan Commitment |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Allowance for credit losses |  |  | $ 11,000 |  |  |  |  |
CapStar Financial Holdings, Inc. |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Shares exchange ratio |  |  |  |  |  | 1.155 |  |
Value of issuance common stock shares |  |  |  |  |  | $ 344,400 |  |
Share price (in dollars per share) | $ / shares |  |  |  |  |  | $ 16.64 |  |
CapStar Financial Holdings, Inc. | CapStar Financial Holdings, Inc. |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |
Assets |  |  |  |  |  |  | $ 3,300,000 |
Total loans |  |  |  |  |  |  | 2,300,000 |
Deposits |  |  |  |  |  |  | $ 2,800,000 |

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