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SECURITIES AND OTHER INVESTMENTS (Amortized Cost of HTM Securities by Security Type and Credit Rating) (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
HTM Securities, Amortized Cost | $ 807,080 | $ 837,378
Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 691,244 | 698,219
Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,150 | 1,166
Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 67,416 | 68,039
Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 47,270 | 69,954
US States and Political Subdivisions Debt Securities [Member] |  |
HTM Securities, Amortized Cost | 695,460 | 699,189
US States and Political Subdivisions Debt Securities [Member] | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 684,805 | 688,499
US States and Political Subdivisions Debt Securities [Member] | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,150 | 1,166
US States and Political Subdivisions Debt Securities [Member] | Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 0 | 0
US States and Political Subdivisions Debt Securities [Member] | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 9,505 | 9,524
Corporate Bond Securities [Member] |  |
HTM Securities, Amortized Cost | 3,484 | 4,349
Corporate Bond Securities [Member] | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 0 | 0
Corporate Bond Securities [Member] | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 0 | 0
Corporate Bond Securities [Member] | Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 0 | 0
Corporate Bond Securities [Member] | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 3,484 | 4,349
Collateralized Mortgage-Backed Securities [Member] |  |
HTM Securities, Amortized Cost | 108,136 | 133,840
Collateralized Mortgage-Backed Securities [Member] | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 6,439 | 9,720
Collateralized Mortgage-Backed Securities [Member] | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 0 | 0
Collateralized Mortgage-Backed Securities [Member] | Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 67,416 | 68,039
Collateralized Mortgage-Backed Securities [Member] | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | $ 34,281 | $ 56,081

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