REVENUES - Consolidated Revenue Information by Geographic Area (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Revenue	$ 2,185	$ 1,898	$ 4,264	$ 3,822
MA
Segment Reporting [Line Items]
Revenue	925	888	1,851	1,747
MA \| Operating Segments
Segment Reporting [Line Items]
Revenue	928	891	1,857	1,753
MIS
Segment Reporting [Line Items]
Revenue	1,260	1,010	2,413	2,075
MIS \| Operating Segments
Segment Reporting [Line Items]
Revenue	1,312	1,060	2,516	2,174
United States
Segment Reporting [Line Items]
Revenue	1,218	992	2,398	2,057
United States \| MA
Segment Reporting [Line Items]
Revenue	409	381	808	756
United States \| MA \| Operating Segments
Segment Reporting [Line Items]
Revenue	409	381	808	756
United States \| MIS
Segment Reporting [Line Items]
Revenue	809	611	1,590	1,301
United States \| MIS \| Operating Segments
Segment Reporting [Line Items]
Revenue	809	611	1,590	1,301
Non-U.S.
Segment Reporting [Line Items]
Revenue	967	906	1,866	1,765
Non-U.S. \| MA
Segment Reporting [Line Items]
Revenue	516	507	1,043	991
Non-U.S. \| MA \| Operating Segments
Segment Reporting [Line Items]
Revenue	516	507	1,043	991
Non-U.S. \| MIS
Segment Reporting [Line Items]
Revenue	451	399	823	774
Non-U.S. \| MIS \| Operating Segments
Segment Reporting [Line Items]
Revenue	451	399	823	774
EMEA
Segment Reporting [Line Items]
Revenue	650	613	1,265	1,182
EMEA \| MA \| Operating Segments
Segment Reporting [Line Items]
Revenue	361	347	735	678
EMEA \| MIS \| Operating Segments
Segment Reporting [Line Items]
Revenue	289	266	530	504
Asia-Pacific
Segment Reporting [Line Items]
Revenue	196	174	373	341
Asia-Pacific \| MA \| Operating Segments
Segment Reporting [Line Items]
Revenue	89	92	181	180
Asia-Pacific \| MIS \| Operating Segments
Segment Reporting [Line Items]
Revenue	107	82	192	161
Americas
Segment Reporting [Line Items]
Revenue	121	119	228	242
Americas \| MA \| Operating Segments
Segment Reporting [Line Items]
Revenue	66	68	127	133
Americas \| MIS \| Operating Segments
Segment Reporting [Line Items]
Revenue	$ 55	$ 51	$ 101	$ 109