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SECURITIES AND OTHER INVESTMENTS (Amortized Cost of HTM Securities by Security Type and Credit Rating) (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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HTM Securities, Amortized Cost | $ 803,851 | $ 837,378
Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 692,671 | 698,219
Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,144 | 1,166
Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 64,595 | 68,039
Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 45,441 | 69,954
US States and Political Subdivisions Debt Securities [Member] |  |
HTM Securities, Amortized Cost | 697,683 | 699,189
US States and Political Subdivisions Debt Securities [Member] | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 686,923 | 688,499
US States and Political Subdivisions Debt Securities [Member] | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,144 | 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 | 9,616 | 9,524
Corporate Bond Securities [Member] |  |
HTM Securities, Amortized Cost | 3,322 | 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 | 3,322 | 4,349
Collateralized Mortgage-Backed Securities [Member] |  |
HTM Securities, Amortized Cost | 102,846 | 133,840
Collateralized Mortgage-Backed Securities [Member] | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 5,748 | 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 | 64,595 | 68,039
Collateralized Mortgage-Backed Securities [Member] | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | $ 32,503 | $ 56,081

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