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PORTFOLIO LOANS - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Net deferred loan origination costs | $ 8,800,000 |  | $ 8,800,000 |  | $ 12,500,000
Net accretable purchase accounting adjustments |  |  | (92,000,000) |  | (8,800,000)
Amount of interest collected and recognized on a cash basis | 0 | $ 0 | 0 | $ 0 |
Commitment to lend | 400,000 |  | 400,000 |  | 0
Collateral dependent loans secured by real estate or business assets | 39,000,000 |  | 39,000,000 |  | $ 19,300,000
Loans in the process of foreclosure | 6,100,000 |  | 6,100,000 |  |
CrossFirst |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
PCD loans acquired and fully reserved at acquisition |  |  | 35,500,000 |  |
90+ Days |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Gross interest income that would have been recorded if impaired loans had been current | 900,000 | 100,000 | 2,100,000 | 600,000 |
Retail loans | CRE |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Loans purchased | $ 0 | $ 0 | 0 | $ 6,900,000 |
Commercial loans | Watch |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Limit above which loans are annually reviewed |  |  | 2,000,000 |  |
Commercial loans | Special Mention |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Limit above which loans are annually reviewed |  |  | 350,000 |  |
Commercial loans | Maximum |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Limit where loans are processed through an expedited underwriting process |  |  | $ 2,000,000 |  |

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