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PORTFOLIO LOANS - Schedule of Financial Instruments Owned and Pledged as Collateral (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Pledged loans | $ 13,424,085 | $ 7,613,683
Total pledged loans |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Pledged loans | 6,992,439 | 5,579,424
FHLB |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Pledged loans | 5,018,506 | 4,813,600
Federal Reserve Bank |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Pledged loans | $ 1,973,933 | $ 765,824

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