INVESTMENT SECURITIES - Schedule of HTM Securities Maturities (Details) - Total AFS Investment Securities - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Amortized Cost
Due within one year	$ 374,998
Due after one year through five years	926,637
Due after five years through ten years	517,827
Due after ten years	2,695,533
Total	4,514,995
Fair Value
Due within one year	382,330
Due after one year through five years	911,651
Due after five years through ten years	480,908
Due after ten years	2,553,425
Total	$ 4,328,314	$ 3,793,952
Weighted- Average Yield
Due within one year	3.90%
Due after one year through five years	4.25%
Due after five years through ten years	3.99%
Due after ten years	4.27%
Total, weighted-average yield	4.20%
Held-to-maturity, accrued interest excluded	$ 47,500	$ 56,700