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PORTFOLIO LOANS - Schedule of financial instruments owned and pledged as collateral (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
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Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Portfolio loans, net | $ 7,496,515 | $ 7,559,294
Asset Pledged as Collateral |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Portfolio loans, net | 5,546,456 | 5,588,395
FHLB |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Portfolio loans, net | 4,821,485 | 4,865,481
Federal Reserve Bank |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Portfolio loans, net | $ 724,971 | $ 722,914

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