INVESTMENT SECURITIES - Debt Maturities (Details) - Investment securities - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Amortized Cost
Due within one year	$ 598,357
Due after one year through five years	2,331,405
Due after five years through ten years	2,491,567
Due after ten years	907,859
Available-for-sale, amortized cost	6,329,188	$ 6,105,116
Fair Value
Due within one year	599,403
Due after one year through five years	2,326,662
Due after five years through ten years	2,407,741
Due after ten years	896,274
Total fair value	$ 6,230,080	$ 5,953,014
Weighted- Average Yield
Due within one year	3.75%
Due after one year through five years	4.10%
Due after five years through ten years	3.82%
Due after ten years	4.71%
Weighted-average yield	4.04%