GOODWILL AND CORE DEPOSIT INTANGIBLES - Schedule of Finite-Lived Intangible Assets, Future Amortization Expense (Details) - Core Deposits - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Intangible Asset, Acquired, Finite-Lived [Line Items]
2026	$ 46
2027	39
2028	34
2029	30
2030	28
Thereafter	18
Balance, net of accumulated amortization	$ 195	$ 249	$ 312

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 of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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