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v3.25.4

Merger, Acquisition, and Divestiture Activity - Additional Information (Details) |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | ---
May 23, 2025 USD ($) shares | May 01, 2025 USD ($) $ / shares | Nov. 25, 2024 USD ($) shares | Apr. 01, 2024 USD ($) | Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($)
Business Combination [Line Items] |  |  |  |  |  |
Purchase price of loans at acquisition |  |  |  | $ 610,700,000 |  |
Par value of acquired loans at acquisition |  |  |  | 679,300,000 |  |
Allowance for credit losses at acquisition |  |  |  | 26,700,000 |  |
Income before income taxes |  |  |  |  | $ 1,093,740,000 | $ 635,364,000
Bremer |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Cash per share above exchange (in dollars per share) | $ / shares |  | $ 26.22 |  |  |  |
Shares exchange ratio |  | 4.182 |  |  |  |
Expected tax deductible amount |  | $ 0 |  |  |  |
Other intangible assets |  | 440,099,000 |  |  |  |
Purchase price of loans at acquisition |  | 1,900,000,000 |  |  | 1,876,226,000 |
Par value of acquired loans at acquisition |  | 2,100,000,000 |  |  | 2,055,598,000 |
Allowance for credit losses at acquisition |  | 103,500,000 |  |  | 103,546,000 |
Acquisition and integration related costs |  |  |  |  | 132,600,000 |
Bremer | Merger-Related Cost |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Income before income taxes |  |  |  |  | (132,600,000) |
Bremer | Provision for Credit Losses On Unfunded Loan Commitments |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Income before income taxes |  |  |  |  | (6,500,000) |
Bremer | Provision For Credit Losses, Loans Acquired |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Income before income taxes |  |  |  |  | (69,100,000) |
Bremer | Benefit Freezing and Subsequent Termination |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Income before income taxes |  |  |  |  | 5,100,000 |
Bremer | Core deposit |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Other intangible assets |  | $ 397,100,000 |  |  |  |
Estimated useful lives of core deposits and customer relationships |  | 10 years |  |  |  |
Bremer | Customer trust relationships |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Other intangible assets |  | $ 43,000,000.0 |  |  |  |
Estimated useful lives of core deposits and customer relationships |  | 12 years |  |  |  |
Bremer | Citibank, N.A |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Forward contract indexed to issuer's equity (in shares) | shares |  |  | 19,047,619 |  |  |
Forward contract indexed to equity, settlement, cash, amount |  |  | $ 400,000,000.0 |  |  |
Bremer | Citigroup Global Markets Inc. |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Forward contract indexed to issuer's equity (in shares) | shares | 21,904,762 |  |  |  |  |
Forward contract indexed to equity, settlement, cash, amount | $ 443,200,000 |  |  |  |  |
Equity interest issued or issuable, additional number of shares to purchase (in shares) | shares |  |  | 2,857,143 |  |  |
Equity interest issued or issuable, additional number of shares (in shares) | shares |  |  | 2,857,143 |  |  |
CapStar Financial Holdings, Inc. |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Other intangible assets |  |  |  | $ 46,125,000 |  |
Purchase price of loans at acquisition |  |  |  |  | 610,691,000 |
Par value of acquired loans at acquisition |  |  |  |  | 679,302,000 |
Allowance for credit losses at acquisition |  |  |  |  | 26,725,000 | 26,700,000
Acquisition and integration related costs |  |  |  |  | $ 3,600,000 | $ 26,300,000
CapStar Financial Holdings, Inc. | Core deposit |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |
Estimated useful lives of core deposits and customer relationships |  |  |  | 10 years |  |

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