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FAIR VALUE - Schedule of Fair Value Option (Details) - Residential Mortgate Loans Held-for-Sale - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Loans held for sale | $ 102 | $ 55
Unpaid Principal Balance | 102 | 54
Difference | $ 0 | $ 1

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