FAIR VALUES OF ASSETS AND LIABILITIES - Fair Value Option-Changes in Fair Value (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Loans held for sale
Fair Value, Option, Quantitative Disclosures [Line Items]
Net gains (losses) from fair value changes	$ 12	$ 9	$ 4	$ 15
Loans held for investment
Fair Value, Option, Quantitative Disclosures [Line Items]
Net gains (losses) from fair value changes	(1)	0	0	(1)
Unsecured debt
Fair Value, Option, Quantitative Disclosures [Line Items]
Net gains (losses) from fair value changes	$ (7)	$ (4)	$ 18	$ (5)

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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