Revenues - Schedule of Changes in the Deferred Revenue Balances (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Change in Contract with Customer, Liability [Abstract]
Beginning Balance	$ 1,075	$ 946
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(923)	(808)
Increases due to amounts billable excluding amounts recognized as revenue during the period	991	946
Increases due to acquisitions during the period	9	16
Effect of exchange rate changes	10	(25)
Total changes in deferred revenue	87	129
Ending Balance	1,162	1,075
Deferred revenue - current	1,050	953
Deferred revenue - noncurrent	112	122
MIS
Change in Contract with Customer, Liability [Abstract]
Beginning Balance	325	334
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(209)	(218)
Increases due to amounts billable excluding amounts recognized as revenue during the period	202	216
Increases due to acquisitions during the period	3	0
Effect of exchange rate changes	1	(7)
Total changes in deferred revenue	(3)	(9)
Ending Balance	322	325
Deferred revenue - current	214	207
Deferred revenue - noncurrent	108	118
MA
Change in Contract with Customer, Liability [Abstract]
Beginning Balance	750	612
Revenue recognized that was included in the deferred revenue balance at the beginning of the period	(714)	(590)
Increases due to amounts billable excluding amounts recognized as revenue during the period	789	730
Increases due to acquisitions during the period	6	16
Effect of exchange rate changes	9	(18)
Total changes in deferred revenue	90	138
Ending Balance	840	750
Deferred revenue - current	836	746
Deferred revenue - noncurrent	$ 4	$ 4