Revenues - Consolidated Revenue Information by Geographic Area (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Revenue	$ 2,079	$ 1,924
MA
Segment Reporting Information [Line Items]
Revenue	926	859
MA | Operating Segments
Segment Reporting Information [Line Items]
Revenue	929	862
MIS
Segment Reporting Information [Line Items]
Revenue	1,153	1,065
MIS | Operating Segments
Segment Reporting Information [Line Items]
Revenue	1,204	1,114
United States
Segment Reporting Information [Line Items]
Revenue	1,180	1,065
United States | MA
Segment Reporting Information [Line Items]
Revenue	399	375
United States | MA | Operating Segments
Segment Reporting Information [Line Items]
Revenue	399	375
United States | MIS
Segment Reporting Information [Line Items]
Revenue	781	690
United States | MIS | Operating Segments
Segment Reporting Information [Line Items]
Revenue	781	690
Non-U.S.
Segment Reporting Information [Line Items]
Revenue	899	859
Non-U.S. | MA
Segment Reporting Information [Line Items]
Revenue	527	484
Non-U.S. | MA | Operating Segments
Segment Reporting Information [Line Items]
Revenue	527	484
Non-U.S. | MIS
Segment Reporting Information [Line Items]
Revenue	372	375
Non-U.S. | MIS | Operating Segments
Segment Reporting Information [Line Items]
Revenue	372	375
EMEA
Segment Reporting Information [Line Items]
Revenue	615	569
EMEA | MA | Operating Segments
Segment Reporting Information [Line Items]
Revenue	374	331
EMEA | MIS | Operating Segments
Segment Reporting Information [Line Items]
Revenue	241	238
Asia-Pacific
Segment Reporting Information [Line Items]
Revenue	177	167
Asia-Pacific | MA | Operating Segments
Segment Reporting Information [Line Items]
Revenue	92	88
Asia-Pacific | MIS | Operating Segments
Segment Reporting Information [Line Items]
Revenue	85	79
Americas
Segment Reporting Information [Line Items]
Revenue	107	123
Americas | MA | Operating Segments
Segment Reporting Information [Line Items]
Revenue	61	65
Americas | MIS | Operating Segments
Segment Reporting Information [Line Items]
Revenue	$ 46	$ 58