INCOME TAXES - Income Tax Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income tax (benefit) expense at the U.S. federal tax rate of 21%						$ (80)	$ (28)	$ (56)
Foreign income tax differential						1	(8)	13
Additional U.S. tax on foreign income						9	(2)	4
State and local income taxes (net of federal effect)						(2)	1	(5)
Other U.S. permanent book/tax differences						5	4	4
Meals and entertainment expense						2	1	1
Nondeductible transaction costs						2	1	0
Nondeductible executive compensation						17	9	13
Dispositions						16	0	0
Spin-off of NCR Atleos						226	0	0
Gains/losses on internal entity restructuring						0	0	55
Excess (benefit)/deficit from share-based payments						2	0	(11)
Change in branch tax status						0	0	1
Research and development tax credits						(2)	(5)	(5)
Foreign tax law changes						(8)	3	(14)
Valuation allowances						20	103	56
Change in liability for unrecognized tax benefits						3	(15)	0
Change in tax estimates for prior periods						(5)	4	17
Other, net						(2)	4	(3)
Total income tax expense (benefit)	$ 185	$ 8	$ 7	$ 15	$ 200	$ 204	$ 72	$ 70