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INVESTMENT SECURITIES - Debt Securities, Held-to-Maturity, Credit Quality Indicator (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | $ 801,324 | $ 991,937
Asset-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 301,284 | 471,996
Agency-guaranteed residential mortgage-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 6,750 | 6,880
Agency-guaranteed commercial mortgage-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 1,708 | 1,770
Agency-guaranteed residential collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 157,231 | 169,754
Agency-guaranteed commercial collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 179,333 | 158,320
Private label collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 155,018 | $ 183,217
AAA |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 97,429 |
AAA | Asset-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AAA | Agency-guaranteed residential mortgage-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AAA | Agency-guaranteed commercial mortgage-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AAA | Agency-guaranteed residential collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AAA | Agency-guaranteed commercial collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AAA | Private label collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 97,429 |
AA |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 9,355 |
AA | Asset-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AA | Agency-guaranteed residential mortgage-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AA | Agency-guaranteed commercial mortgage-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AA | Agency-guaranteed residential collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AA | Agency-guaranteed commercial collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 0 |
AA | Private label collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 9,355 |
Not Rated |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 694,540 |
Not Rated | Asset-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 301,284 |
Not Rated | Agency-guaranteed residential mortgage-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 6,750 |
Not Rated | Agency-guaranteed commercial mortgage-backed securities |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 1,708 |
Not Rated | Agency-guaranteed residential collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 157,231 |
Not Rated | Agency-guaranteed commercial collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | 179,333 |
Not Rated | Private label collateralized mortgage obligations |  |
Schedule of Held-to-Maturity Securities [Line Items] |  |
Investment securities held to maturity | $ 48,234 |

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