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