PREMISES AND EQUIPMENT - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 276	$ 225	$ 142
Software and related projects
Property, Plant and Equipment [Line Items]
Impairment charges	22	35
Software and related projects \| Acquisition-related expenses
Property, Plant and Equipment [Line Items]
Impairment charges	$ 9	$ 32

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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- References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

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