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BUSINESS COMBINATION - Preliminary Purchase Price Allocation and Assets Acquired and Liabilities (Details) - USD ($) $ in Thousands |  | 3 Months Ended
--- | --- | ---
Sep. 02, 2025 | Mar. 31, 2026
Fair value of liabilities assumed: |  |
Bargain purchase gain |  | $ 0
Mechanics Bank Acquisition |  |
Net assets identified |  |
Purchase price consideration | $ 265,803 |
Fair value of assets acquired: |  |
Cash and cash equivalents | 156,890 |
Total investment securities | 1,028,627 |
Loans held for sale | 39,489 |
Loans held for investment | 5,645,715 |
Allowance for credit losses | (83,746) |
Mortgage servicing rights | 89,533 |
Premises and equipment | 31,979 |
Other intangible assets, net | 190,913 |
Deferred tax assets | 59,960 |
Other assets | 283,526 |
Total assets acquired | 7,442,886 |
Fair value of liabilities assumed: |  |
Deposits | 5,743,725 |
FHLB advances | 1,005,370 |
Long-term debt | 193,466 |
Accrued interest payable and other liabilities | 89,062 |
Total liabilities assumed | 7,031,623 |
Net assets acquired | 411,263 |
Bargain purchase gain | 145,460 |
Mechanics Bank Acquisition | Core deposit intangibles |  |
Fair value of liabilities assumed: |  |
Intangible assets acquired in merger, core deposits | 90,800 |
Mechanics Bank Acquisition | DUS License |  |
Fair value of liabilities assumed: |  |
Intangible assets acquired | $ 100,200 |

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