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v3.25.3

Acquisition and Divestiture Activity - Additional Information (Details) |  |  |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | --- | --- | ---
May 23, 2025 USD ($) shares | May 01, 2025 USD ($) $ / shares | Nov. 25, 2024 USD ($) shares | Apr. 01, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($)
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 |  |  |  |
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 |  | 1,876,520,000 |  |  |  |  |  |
Par value of acquired loans at acquisition |  | 2,055,948,000 |  |  |  |  |  |
Allowance for credit losses at acquisition |  | 103,546,000 |  |  | $ 103,500,000 |  |  |
Transaction costs, expensed |  |  |  |  | 67,000,000.0 |  | $ 108,000,000.0 |
Payments for merger related costs |  |  |  |  | 67,000,000.0 |  | 108,000,000.0 |
Business combination, provisional information, initial accounting incomplete, adjustment, financial liabilities |  |  |  |  |  |  | 6,500,000 |
Business combination, provisional information, initial accounting incomplete, adjustment, financial assets |  |  |  |  |  |  | 69,100,000 |
Adjustment, freezing of benefits |  |  |  |  |  |  | 21,000,000.0 |
Bremer | Core deposit |  |  |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |  |  |
Other intangible assets |  | $ 397,100,000 |  |  |  |  |  |
Estimated useful lives |  | 10 years |  |  |  |  |  |
Bremer | Customer relationship |  |  |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |  |  |
Other intangible assets |  | $ 43,000,000.0 |  |  |  |  |  |
Estimated useful lives |  | 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 |  |  | $ 400,000,000 |  |  |  |  |
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 | $ 443,200,000 |  |  |  |  |  |  |
Additional number of shares to purchase (in shares) | shares |  |  | 2,857,143 |  |  |  |  |
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 |  |  |  |
Transaction costs, expensed |  |  |  |  | $ 2,200,000 | $ 6,900,000 | $ 3,600,000 | $ 29,200,000
CapStar Financial Holdings, Inc. | Core deposit |  |  |  |  |  |  |  |
Business Combination [Line Items] |  |  |  |  |  |  |  |
Estimated useful lives |  |  |  | 10 years |  |  |  |

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- Definition The amount of cash paid during the reporting period for charges associated with the mergers. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 25 -Subparagraph (g) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-25 + Details
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