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SECURITIES AND OTHER INVESTMENTS (Amortized Cost of HTM Securities by Security Type and Credit Rating) (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
HTM Securities, Amortized Cost | $ 828,928 | $ 837,378
Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 694,459 | 698,219
Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,160 | 1,166
Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 67,305 | 68,039
Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 66,004 | 69,954
Obligations of states and political subdivisions |  |
HTM Securities, Amortized Cost | 695,952 | 699,189
Obligations of states and political subdivisions | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 685,273 | 688,499
Obligations of states and political subdivisions | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,160 | 1,166
Obligations of states and political subdivisions | Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 0 | 0
Obligations of states and political subdivisions | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 9,519 | 9,524
Corporate and other bonds |  |
HTM Securities, Amortized Cost | 4,230 | 4,349
Corporate and other bonds | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 0 | 0
Corporate and other bonds | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 0 | 0
Corporate and other bonds | Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 0 | 0
Corporate and other bonds | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 4,230 | 4,349
Mortgage-backed securities |  |
HTM Securities, Amortized Cost | 128,746 | 133,840
Mortgage-backed securities | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 9,186 | 9,720
Mortgage-backed securities | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 0 | 0
Mortgage-backed securities | Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 67,305 | 68,039
Mortgage-backed securities | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | $ 52,255 | $ 56,081

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