GOODWILL AND CORE DEPOSIT INTANGIBLES - Schedule of Gross Carrying Amount and Accumulated Amortization of Core Deposit Intangibles (Details) - Core Deposits - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Intangible Asset, Acquired, Finite-Lived [Line Items]
Gross balance	$ 501	$ 501
Less: accumulated amortization	280	252
Balance, net of accumulated amortization	$ 221	$ 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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