GOODWILL AND CORE DEPOSIT INTANGIBLES - Schedule of Finite-Lived Intangible Assets, Future Amortization Expense (Details) - Core deposit intangibles - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Acquired Finite-Lived Intangible Assets [Line Items]
Remainder 2025	$ 39
2026	46
2027	39
2028	34
2029	30
2030	28
Thereafter	18
Balance, net of accumulated amortization	$ 234	$ 249

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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