GOODWILL AND CORE DEPOSIT INTANGIBLES - Schedule of Finite-Lived Intangible Assets, Future Amortization Expense (Details) - Core Deposits - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Intangible Asset, Acquired, Finite-Lived [Line Items]
Remainder 2026	$ 33
2027	39
2028	34
2029	30
2030	28
2031	18
Balance, net of accumulated amortization	$ 182	$ 195

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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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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