Goodwill and Other Identifiable Intangible Assets (Additional Information) (Details) - USD ($) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2023	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Line Items]
Goodwill, impairment loss				$ 158
Goodwill	$ 6,200			6,200	$ 6,078	$ 6,248
Goodwill, accumulated impairment loss	158			158
Impairment of intangible assets, indefinite-lived (excluding goodwill)				2	4
Impairment and other-related charges, net		$ 290	$ 147	160	245	21
Aggregate amortization expense of identifiable intangible assets				167	$ 166	$ 172
Accelerated amortization expense	6
Traffic Solutions
Goodwill [Line Items]
Goodwill, impairment loss				158
Goodwill	$ 391			$ 391