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v3.25.1

ACQUISITIONS (Narrative) (Details) $ in Thousands, shares in Millions |  |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | --- | ---
Apr. 01, 2025 shares | Apr. 01, 2024 USD ($) item shares | Mar. 31, 2025 USD ($) | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($)
Business Acquisition [Line Items] |  |  |  |  |
Goodwill |  |  | $ 1,214,053 |  | $ 1,214,053
Merger-related costs |  |  | 4,940 | $ 1,874 |
American National |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Conversion ratio |  | 0.00135 |  |  |
Additional shares issued | shares |  | 14.3 |  |  |
Purchase price consideration |  | $ 505,473 |  |  |
Number of branches acquired | item |  | 26 |  |  |
Goodwill |  | $ 288,842 | 288,800 |  |
Increase in goodwill |  |  |  |  | $ 6,500
Accretion expense |  |  | 0 | 5,000 |
Merger-related costs |  |  |  | $ 1,600 |
American National | Wholesale Banking |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Goodwill |  | 210,800 |  |  |
American National | Consumer Banking |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Goodwill |  | $ 78,000 |  |  |
Sandy Spring |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Conversion ratio | 0.9 |  |  |  |
Additional shares issued | shares | 41.0 |  |  |  |
Purchase price consideration |  |  | 1,300,000 |  |
Merger-related costs |  |  | $ 4,600 |  |

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