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ACQUISITIONS (Narrative) (Details) $ in Thousands, shares in Millions |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 01, 2024 USD ($) item shares | Dec. 31, 2024 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |
Purchase price consideration |  |  |  | $ 505,746 |  |
Goodwill |  | $ 1,214,053 |  | 1,214,053 | $ 925,211 |
Increase in goodwill |  | 1,300 | $ 5,200 |  |  |
Merger-related costs |  |  |  | 40,018 | 2,995 |
American National |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Conversion ratio | 1.35% |  |  |  |  |
Additional shares issued | shares | 14.3 |  |  |  |  |
Purchase price consideration | $ 505,473 |  |  |  |  |
Number of branches acquired | item | 26 |  |  |  |  |
Goodwill | $ 288,842 | 288,842 |  | 288,842 | 0 |
Increase in goodwill |  |  |  | 6,500 |  |
Accretion expense |  |  |  | 5,000 | 19,700 | $ 19,700
Merger-related costs |  |  |  | 33,500 | $ 2,900 | $ 0
American National | Wholesale Banking |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Goodwill |  | 210,800 |  | 210,800 |  |
American National | Consumer Banking |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Goodwill |  | $ 78,000 |  | $ 78,000 |  |

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