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v3.25.1

GOODWILL AND INTANGIBLE ASSETS (Narrative) (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2025 USD ($) segment | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($) | Apr. 01, 2024 USD ($)
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Number of operating segments | segment | 2 |  |  |
Goodwill | $ 1,214,053,000 |  | $ 1,214,053,000 |
Intangible Assets | 79,165,000 |  | 84,563,000 |
Impairment of goodwill or intangible assets | 0 |  |  |
Intangible assets, amortization expense | $ 5,398,000 | $ 1,895,000 |  |
Core Deposits [Member] | Minimum [Member] |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Intangible assets, amortization period (years) | 4 years |  |  |
Core Deposits [Member] | Maximum [Member] |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Intangible assets, amortization period (years) | 10 years |  |  |
Other Intangible Assets [Member] | Minimum [Member] |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Intangible assets, amortization period (years) | 4 years |  |  |
Other Intangible Assets [Member] | Maximum [Member] |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Intangible assets, amortization period (years) | 10 years |  |  |
American National |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Goodwill | $ 288,800,000 |  |  | $ 288,842,000
Increase in goodwill |  |  | $ 6,500,000 |
American National | Wholesale Banking |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Goodwill |  |  |  | 210,800,000
American National | Consumer Banking |  |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |  |
Goodwill |  |  |  | $ 78,000,000

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