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SHAREHOLDERS' EQUITY AND DIVIDEND LIMITATIONS (Details) | Mar. 31, 2026 shares | Dec. 31, 2025 shares | Sep. 02, 2025 shares | Sep. 01, 2025 shares
--- | --- | --- | --- | ---
Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Common stock, shares authorized (in shares) |  |  | 1,900,000,000 | 160,000,000
Preferred Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Preferred stock, shares authorized (in shares) |  |  | 120,000 | 100,000
Common Class A |  |  |  |
Class of Stock [Line Items] |  |  |  |
Common stock, shares authorized (in shares) | 1,897,500,000 | 1,897,500,000 | 1,897,500,000 |
Common stock, shares outstanding (in shares) | 220,286,142 | 220,190,561 |  |
Common Class A | Mechanics Bank Acquisition |  |  |  |
Class of Stock [Line Items] |  |  |  |
Business combination, fixed exchange ratio |  |  | 3,301.092 |
Common Class B |  |  |  |
Class of Stock [Line Items] |  |  |  |
Common stock, shares authorized (in shares) | 2,500,000 | 2,500,000 | 2,500,000 |
Common stock, shares outstanding (in shares) | 1,114,448 | 1,114,448 |  |
Common Class B | Mechanics Bank Acquisition |  |  |  |
Class of Stock [Line Items] |  |  |  |
Business combination, fixed exchange ratio |  |  | 330.1092 |
Voting Common Stock | Mechanics Bank Acquisition |  |  |  |
Class of Stock [Line Items] |  |  |  |
Business combination, fixed exchange ratio |  |  | 3,301.092 |
Nonvoting Common Stock | Mechanics Bank Acquisition |  |  |  |
Class of Stock [Line Items] |  |  |  |
Business combination, fixed exchange ratio |  |  | 330.1092 |

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