FAIR VALUE MEASUREMENTS - Residential Mortgage and Commercial Real Estate Loans Held For Sale (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Aggregate Fair Value	$ 1,334	$ 858
Level 2 \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Aggregate Fair Value	592	633
Aggregate Unpaid Principal	573	625
Aggregate Fair Value Greater (Less) Than Aggregate Unpaid Principal	19	8
Level 2 \| Commercial loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Aggregate Fair Value	176	192
Aggregate Unpaid Principal	186	199
Aggregate Fair Value Greater (Less) Than Aggregate Unpaid Principal	$ (10)	$ (7)

The aggregate unpaid principal balance of loans measured at fair value.

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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.

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

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- Definition

Amount, before valuation allowance, of financing receivable classified as held-for-sale.

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