INVESTMENT SECURITIES - Debt Maturities (Details) - Investment securities - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Amortized Cost
Due within one year	$ 624,237
Due after one year through five years	2,483,319
Due after five years through ten years	2,629,374
Due after ten years	1,019,255
Available-for-sale, amortized cost	6,756,185	$ 6,105,116
Fair Value
Due within one year	625,265
Due after one year through five years	2,483,600
Due after five years through ten years	2,558,256
Due after ten years	1,006,910
Total fair value	$ 6,674,031	$ 5,953,014
Weighted- Average Yield
Due within one year	4.23%
Due after one year through five years	4.07%
Due after five years through ten years	3.83%
Due after ten years	4.78%
Weighted-average yield	4.10%