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SECURITIES (Amortized Cost of HTM Securities by Security Type and Credit Rating) (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
HTM Securities, Amortized Cost | $ 843,269 | $ 847,732
Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 699,170 | 707,505
Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,171 | 1,187
Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 68,561 | 72,412
Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 74,367 | 66,628
U.S. government and agency securities |  |
HTM Securities, Amortized Cost | 0 | 687
U.S. government and agency securities | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 0 | 0
U.S. government and agency securities | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 0 | 0
U.S. government and agency securities | Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 0 | 687
U.S. government and agency securities | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 0 | 0
Obligations of states and political subdivisions |  |
HTM Securities, Amortized Cost | 700,400 | 705,990
Obligations of states and political subdivisions | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 689,699 | 704,803
Obligations of states and political subdivisions | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,171 | 1,187
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 | 9,530 | 0
Corporate and other bonds |  |
HTM Securities, Amortized Cost | 4,536 | 5,159
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 | 4,536 | 5,159
Mortgage-backed securities |  |
HTM Securities, Amortized Cost | 138,333 | 135,896
Mortgage-backed securities | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 9,471 | 2,702
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 | 68,561 | 71,725
Mortgage-backed securities | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | $ 60,301 | $ 61,469

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