DISCONTINUED OPERATIONS, SIGNIFICANT DISPOSALS AND OTHER BUSINESS EXITS - Wind Down Charges (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended			16 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)	$ 780	$ 781	$ 0	$ 0
Russian Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		27			$ 63
Estimated additional charges	58	58			58
Russian Operations | All Other
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		23			54
Estimated additional charges	56	56			56
Russian Operations | Services, Markets and Banking
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		4			9
Estimated additional charges	2	2			2
Employee Severance Costs
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		687
Employee Severance Costs | Russian Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		15			44
Estimated additional charges	22	22			22
Employee Severance Costs | Russian Operations | All Other
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		11			35
Estimated additional charges	20	20			20
Employee Severance Costs | Russian Operations | Services, Markets and Banking
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		4			9
Estimated additional charges	2	2			2
Vendor termination and other costs | Russian Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		12			19
Estimated additional charges	36	36			36
Vendor termination and other costs | Russian Operations | All Other
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		12			19
Estimated additional charges	36	36			36
Vendor termination and other costs | Russian Operations | Services, Markets and Banking
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Additional charges (releases)		0			0
Estimated additional charges	$ 0	$ 0			$ 0