MORTGAGE LOAN SALES AND SERVICING RIGHTS - Residential Mortgage Portfolio (Details) - Residential mortgage - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Servicing Asset at Amortized Cost [Line Items]
Residential mortgage loans sold with servicing retained	$ 1,514	$ 1,150	$ 3,691	$ 2,944
Pretax gains resulting from above loan sales	24	17	66	49
Total servicing, late, and other ancillary fees	$ 27	$ 27	$ 80	$ 78