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v3.25.0.1

Merger, Acquisition, and Divestiture Activity - Additional Information (Details) $ / shares in Units, $ in Thousands |  |  |  | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Nov. 25, 2024 USD ($) $ / shares shares | Apr. 01, 2024 USD ($) | Nov. 18, 2022 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Feb. 15, 2022 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |  |
Purchase price of loans at acquisition |  | $ 610,700 |  | $ 610,691 |  |  |
Par value of acquired loans at acquisition |  | 679,300 |  | 679,302 |  |  |
Allowance for credit losses at acquisition |  | 26,700 |  | 26,725 |  |  |
Plan assets |  |  |  | 0 | $ 0 |  |
Deposits, health savings accounts |  |  | $ 382,000 |  |  |  |
Gain on sale of health savings accounts |  |  | $ 90,700 | 0 | 0 | $ 90,673 |
Property optimization |  |  |  | 0 | 1,559 | 26,818 |
Assets |  |  |  | 53,552,272 | 49,089,836 |  |
Total loans |  |  |  | 36,285,887 | 32,991,927 |  |
Deposits |  |  |  | 40,823,560 | 37,235,180 |  |
Bremer |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Assets |  |  |  | 16,500,000 |  |  |
Total loans |  |  |  | 11,800,000 |  |  |
Deposits |  |  |  | 13,200,000 |  |  |
CapStar Financial Holdings, Inc. |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Other intangible assets |  | 46,125 |  |  |  |  |
Allowance for credit losses at acquisition |  | $ 26,700 |  |  |  |  |
Acquisition and integration related costs |  |  |  | 26,300 |  |  |
CapStar Financial Holdings, Inc. | Core deposit |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Estimated useful lives of core deposits and customer relationships |  | 10 years |  |  |  |  |
First Midwest |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Other intangible assets |  |  |  |  |  |  | $ 117,584
Transaction costs, expensed |  |  |  | 8,500 | $ 28,700 | $ 120,900 |
Bremer |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Shares exchange ratio | 4.182 |  |  |  |  |  |
Cash per share above exchange (in dollars per share) | $ / shares | $ 26.22 |  |  |  |  |  |
Value of issuance common stock shares | $ 1,400,000 |  |  |  |  |  |
Price per share (in dollars per share) | $ / shares | $ 116.76 |  |  |  |  |  |
Transaction costs |  |  |  | $ 2,500 |  |  |
Bremer | Citibank, N.A |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Shares | shares | 19,047,619 |  |  |  |  |  |
Forward Contract Indexed to Equity, Settlement, Cash, Amount | $ 400,000 |  |  |  |  |  |
Bremer | Citigroup Global Markets Inc. |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Business Acquisition, Equity Interest Issued or Issuable, Period For Additional Purchases | 30 days |  |  |  |  |  |
Business Acquisition, Equity Interest Issued or Issuable, Additional Number of Shares To Purchase | shares | 2,857,143 |  |  |  |  |  |
Business Acquisition, Equity Interest Issued or Issuable, Additional Number of Shares | shares | 2,857,143 |  |  |  |  |  |

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