FAIR VALUE MEASUREMENTS - Residential Mortgage and Commercial Real Estate Loans Held For Sale (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Aggregate Fair Value	$ 1,537	$ 1,198
Level 2 \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Aggregate Fair Value	778	895
Aggregate Unpaid Principal	770	872
Aggregate Fair Value Greater (Less) Than Aggregate Unpaid Principal	8	23
Level 2 \| Commercial loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Aggregate Fair Value	139	170
Aggregate Unpaid Principal	147	185
Aggregate Fair Value Greater (Less) Than Aggregate Unpaid Principal	$ (8)	$ (15)

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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