OPERATING SEGMENTS - Reconciliation (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
	Mar. 01, 2023	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting Information [Line Items]
Income (loss) from continuing operations		$ 3,263		$ 2,952		$ 6,671	$ 7,604
Total revenues, net of interest expense		6,646		5,536		14,243	13,635
Total operating expenses		13,353		13,570		27,548	26,859
Provision (benefits) for income taxes		1,047		1,090		2,183	2,621
Held for sale | Mexico and Asia Exit Markets
Segment Reporting Information [Line Items]
Operating expenses, before tax		85	$ 110	79
Operating expenses, after tax		58	$ 77	57
Sold | India
Segment Reporting Information [Line Items]
Operating expenses, before tax					$ 1,059
Operating expenses, after tax					$ 727
Pretax gain (loss) on sale of business	$ 1,000
Gain (loss) on sale of business, after-tax	$ 717
Operating Segments
Segment Reporting Information [Line Items]
Income (loss) from continuing operations		3,295		3,044		6,797	7,048
Reconciling Items
Segment Reporting Information [Line Items]
Income (loss) from continuing operations		(32)		(92)		(126)	556
Total revenues, net of interest expense		33		(6)		21	1,012
Total operating expenses		85		79		195	152
Provision (release) for credit losses		(3)		(12)		8	(20)
Provision (benefits) for income taxes		$ (17)		$ 19		$ (56)	$ 324