LOANS - Interest Income Recognized for Non-Accrual Consumer Loans (Details) - Consumer loans - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized	$ 7	$ 6	$ 19	$ 20
Loans sold and/or reclassified to held-for-sale	12	2	54	61
Credit card portfolio loans		700
In North America offices
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized	4	4	11	12
In offices outside North America
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized	3	2	8	8
Residential mortgages | In North America offices
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized	3	2	7	7
Residential mortgages | In offices outside North America
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized	3	2	7	7
Home equity loans | In North America offices
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized	1	1	3	4
Personal, small business and other | In North America offices
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized	0	1	1	1
Personal, small business and other | In offices outside North America
Financing Receivable, Nonaccrual [Line Items]
Interest income recognized	$ 0	$ 0	$ 1	$ 1