SECURITIES AND OTHER INVESTMENTS (Amortized Cost of HTM Securities by Security Type and Credit Rating) (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
HTM Securities, Amortized Cost	$ 807,080	$ 837,378
Moody's AAA/AA/A
HTM Securities, Amortized Cost	691,244	698,219
Moody's BBB/BB/B
HTM Securities, Amortized Cost	1,150	1,166
Moody's Not Rated - Agency
HTM Securities, Amortized Cost	67,416	68,039
Moody's Not Rated - Non-Agency
HTM Securities, Amortized Cost	47,270	69,954
US States and Political Subdivisions Debt Securities [Member]
HTM Securities, Amortized Cost	695,460	699,189
US States and Political Subdivisions Debt Securities [Member] | Moody's AAA/AA/A
HTM Securities, Amortized Cost	684,805	688,499
US States and Political Subdivisions Debt Securities [Member] | Moody's BBB/BB/B
HTM Securities, Amortized Cost	1,150	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	9,505	9,524
Corporate Bond Securities [Member]
HTM Securities, Amortized Cost	3,484	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	3,484	4,349
Collateralized Mortgage-Backed Securities [Member]
HTM Securities, Amortized Cost	108,136	133,840
Collateralized Mortgage-Backed Securities [Member] | Moody's AAA/AA/A
HTM Securities, Amortized Cost	6,439	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	67,416	68,039
Collateralized Mortgage-Backed Securities [Member] | Moody's Not Rated - Non-Agency
HTM Securities, Amortized Cost	$ 34,281	$ 56,081