Basis of Presentation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reclassification [Line Items]
Revenue	$ 460	$ 454	$ 1,442	$ 1,345
Cost of revenue	$ 185	200	$ 550	610
Reclassification Adjustment | Reclassification, from Recurring Services to Consulting Services
Reclassification [Line Items]
Revenue		28		80
Cost of revenue		21		62
Reclassification Adjustment | Reclassification, from Recurring Services to Perpetual Software Hardware and Other
Reclassification [Line Items]
Revenue		8		25
Cost of revenue		$ 6		$ 19