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SECURITIES (Amortized Cost of HTM Securities by Security Type and Credit Rating) (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
HTM Securities, Amortized Cost | $ 535,722 | $ 544,851
Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 528,157 | 532,157
Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 7,565 | 8,084
Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost |  | 4,610
U.S. government and agency securities |  |
HTM Securities, Amortized Cost | 2,637 | 2,751
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 Not Rated - Agency |  |
HTM Securities, Amortized Cost | 2,637 | 2,751
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 | 528,157 | 536,767
Obligations of states and political subdivisions | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 528,157 | 532,157
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 | 0 | 4,610
Mortgage-backed securities |  |
HTM Securities, Amortized Cost | 4,928 | 5,333
Mortgage-backed securities | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 0 | 0
Mortgage-backed securities | Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 4,928 | 5,333
Mortgage-backed securities | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | $ 0 | $ 0

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