INVESTMENT SECURITIES - Schedule of Amortized Cost and Estimated Fair Value of Debt Securities, Available for Sale, by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Amortized Cost
Due in one year or less	$ 331,452
Due from one year to five years	436,955
Due from five to ten years	9,253
Due after ten years	48,964
Mortgage-backed securities	621,013
Debt securities, available-for-sale, amortized cost, total	1,447,637	$ 1,559,005
Estimated Fair Value
Due in one year or less	329,133
Due from one year to five years	426,410
Due from five to ten years	8,764
Due after ten years	47,149
Mortgage-backed securities	591,488
Debt securities, available-for-sale, estimated fair value, total	1,402,944	1,500,060
Amortized Cost
Due in one year or less	0
Due from one year to five years	0
Due from five to ten years	0
Due after ten years	31,905
Mortgage-backed securities	109,607
Amortized Cost	141,512	134,864
Estimated Fair Value
Due in one year or less	0
Due from one year to five years	0
Due from five to ten years	0
Due after ten years	26,854
Due after ten years	95,877
Estimated Fair Value	$ 122,731	$ 114,538