Revenues - Schedule of Changes in the Deferred Revenue Balances (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Change in Contract with Customer, Liability [Abstract]
Beginning Balance	$ 1,452	$ 1,366	$ 1,333	$ 1,335
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(626)	(590)	(1,161)	(1,069)
Increases due to amounts billable excluding amounts recognized as revenue during the period	492	471	1,126	1,037
Increases due to acquisitions during the period			0	1
Effect of exchange rate changes	(27)	(14)	(7)	(71)
Total changes in deferred revenue	(161)	(133)	(42)	(102)
Ending Balance	1,291	1,233	1,291	1,233
Deferred revenue	1,226	1,155	1,226	1,155	$ 1,258
Non-current portion of deferred revenue	65	78	65	78	$ 75
MA
Change in Contract with Customer, Liability [Abstract]
Beginning Balance	1,116	1,019	1,055	1,039
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(513)	(480)	(969)	(883)
Increases due to amounts billable excluding amounts recognized as revenue during the period	410	389	908	819
Increases due to acquisitions during the period			0	1
Effect of exchange rate changes	(25)	(9)	(6)	(57)
Total changes in deferred revenue	(128)	(100)	(67)	(120)
Ending Balance	988	919	988	919
Deferred revenue	986	917	986	917
Non-current portion of deferred revenue	2	2	2	2
MIS
Change in Contract with Customer, Liability [Abstract]
Beginning Balance	336	347	278	296
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(113)	(110)	(192)	(186)
Increases due to amounts billable excluding amounts recognized as revenue during the period	82	82	218	218
Increases due to acquisitions during the period			0	0
Effect of exchange rate changes	(2)	(5)	(1)	(14)
Total changes in deferred revenue	(33)	(33)	25	18
Ending Balance	303	314	303	314
Deferred revenue	240	238	240	238
Non-current portion of deferred revenue	$ 63	$ 76	$ 63	$ 76