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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, 2025 | Dec. 31, 2024
--- | --- | ---
HTM Securities, Amortized Cost | $ 821,059 | $ 803,851
Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 715,557 | 692,671
Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,139 | 1,144
Moody's Not Rated - Agency |  |
HTM Securities, Amortized Cost | 64,044 | 64,595
Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | 40,319 | 45,441
US States and Political Subdivisions Debt Securities [Member] |  |
HTM Securities, Amortized Cost | 720,888 | 697,683
US States and Political Subdivisions Debt Securities [Member] | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 710,141 | 686,923
US States and Political Subdivisions Debt Securities [Member] | Moody's BBB/BB/B |  |
HTM Securities, Amortized Cost | 1,139 | 1,144
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 | 9,608 | 9,616
Corporate Bond Securities [Member] |  |
HTM Securities, Amortized Cost | 3,087 | 3,322
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 | 3,087 | 3,322
Collateralized Mortgage-Backed Securities [Member] |  |
HTM Securities, Amortized Cost | 97,084 | 102,846
Collateralized Mortgage-Backed Securities [Member] | Moody's AAA/AA/A |  |
HTM Securities, Amortized Cost | 5,416 | 5,748
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 | 64,044 | 64,595
Collateralized Mortgage-Backed Securities [Member] | Moody's Not Rated - Non-Agency |  |
HTM Securities, Amortized Cost | $ 27,624 | $ 32,503

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