Segment and Related Information - Schedule of Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Revenue	$ 4,146	$ 3,755	$ 8,318	$ 7,532
Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	895	745	1,874	1,595
Services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	3,251	3,010	6,444	5,937
Subscription
Disaggregation of Revenue [Line Items]
Revenue	2,064	1,954	4,077	3,851
Non-subscription / Transaction
Disaggregation of Revenue [Line Items]
Revenue	895	745	1,874	1,595
Non-transaction
Disaggregation of Revenue [Line Items]
Revenue	540	502	1,079	983
Asset-linked fees
Disaggregation of Revenue [Line Items]
Revenue	348	286	688	574
Sales usage-based royalties
Disaggregation of Revenue [Line Items]
Revenue	126	110	259	221
Recurring variable revenue
Disaggregation of Revenue [Line Items]
Revenue	173	158	341	308
Reportable Legal Entities
Disaggregation of Revenue [Line Items]
Revenue	4,199	3,804	8,422	7,629
Reportable Legal Entities \| Market Intelligence
Disaggregation of Revenue [Line Items]
Revenue	1,290	1,217	2,586	2,416
Reportable Legal Entities \| Market Intelligence \| Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	41	42	117	98
Reportable Legal Entities \| Market Intelligence \| Services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	1,249	1,175	2,469	2,318
Reportable Legal Entities \| Market Intelligence \| Subscription
Disaggregation of Revenue [Line Items]
Revenue	1,076	1,017	2,128	2,010
Reportable Legal Entities \| Market Intelligence \| Non-subscription / Transaction
Disaggregation of Revenue [Line Items]
Revenue	41	42	117	98
Reportable Legal Entities \| Market Intelligence \| Non-transaction
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Market Intelligence \| Asset-linked fees
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Market Intelligence \| Sales usage-based royalties
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Market Intelligence \| Recurring variable revenue
Disaggregation of Revenue [Line Items]
Revenue	173	158	341	308
Reportable Legal Entities \| Ratings
Disaggregation of Revenue [Line Items]
Revenue	1,339	1,148	2,641	2,297
Reportable Legal Entities \| Ratings \| Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	746	597	1,458	1,217
Reportable Legal Entities \| Ratings \| Services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	593	551	1,183	1,080
Reportable Legal Entities \| Ratings \| Subscription
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Ratings \| Non-subscription / Transaction
Disaggregation of Revenue [Line Items]
Revenue	746	597	1,458	1,217
Reportable Legal Entities \| Ratings \| Non-transaction
Disaggregation of Revenue [Line Items]
Revenue	593	551	1,183	1,080
Reportable Legal Entities \| Ratings \| Asset-linked fees
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Ratings \| Sales usage-based royalties
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Ratings \| Recurring variable revenue
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Energy
Disaggregation of Revenue [Line Items]
Revenue	568	555	1,221	1,167
Reportable Legal Entities \| Energy \| Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	23	25	132	122
Reportable Legal Entities \| Energy \| Services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	545	530	1,089	1,045
Reportable Legal Entities \| Energy \| Subscription
Disaggregation of Revenue [Line Items]
Revenue	518	500	1,024	986
Reportable Legal Entities \| Energy \| Non-subscription / Transaction
Disaggregation of Revenue [Line Items]
Revenue	23	25	132	122
Reportable Legal Entities \| Energy \| Non-transaction
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Energy \| Asset-linked fees
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Energy \| Sales usage-based royalties
Disaggregation of Revenue [Line Items]
Revenue	27	30	65	59
Reportable Legal Entities \| Energy \| Recurring variable revenue
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Mobility
Disaggregation of Revenue [Line Items]
Revenue	468	438	921	858
Reportable Legal Entities \| Mobility \| Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	85	81	167	158
Reportable Legal Entities \| Mobility \| Services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	383	357	754	700
Reportable Legal Entities \| Mobility \| Subscription
Disaggregation of Revenue [Line Items]
Revenue	383	357	754	700
Reportable Legal Entities \| Mobility \| Non-subscription / Transaction
Disaggregation of Revenue [Line Items]
Revenue	85	81	167	158
Reportable Legal Entities \| Mobility \| Non-transaction
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Mobility \| Asset-linked fees
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Mobility \| Sales usage-based royalties
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Mobility \| Recurring variable revenue
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Indices
Disaggregation of Revenue [Line Items]
Revenue	534	446	1,053	891
Reportable Legal Entities \| Indices \| Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Indices \| Services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	534	446	1,053	891
Reportable Legal Entities \| Indices \| Subscription
Disaggregation of Revenue [Line Items]
Revenue	87	80	171	155
Reportable Legal Entities \| Indices \| Non-subscription / Transaction
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Indices \| Non-transaction
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Reportable Legal Entities \| Indices \| Asset-linked fees
Disaggregation of Revenue [Line Items]
Revenue	348	286	688	574
Reportable Legal Entities \| Indices \| Sales usage-based royalties
Disaggregation of Revenue [Line Items]
Revenue	99	80	194	162
Reportable Legal Entities \| Indices \| Recurring variable revenue
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination
Disaggregation of Revenue [Line Items]
Revenue	(53)	(49)	(104)	(97)
Intersegment Elimination \| Services transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination \| Services transferred over time
Disaggregation of Revenue [Line Items]
Revenue	(53)	(49)	(104)	(97)
Intersegment Elimination \| Subscription
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination \| Non-subscription / Transaction
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination \| Non-transaction
Disaggregation of Revenue [Line Items]
Revenue	(53)	(49)	(104)	(97)
Intersegment Elimination \| Asset-linked fees
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination \| Sales usage-based royalties
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination \| Recurring variable revenue
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination \| Market Intelligence
Disaggregation of Revenue [Line Items]
Revenue	(4)	(3)	(7)	(6)
Intersegment Elimination \| Ratings
Disaggregation of Revenue [Line Items]
Revenue	(46)	(43)	(91)	(85)
Intersegment Elimination \| Energy
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination \| Mobility
Disaggregation of Revenue [Line Items]
Revenue	0	0	0	0
Intersegment Elimination \| Indices
Disaggregation of Revenue [Line Items]
Revenue	$ (3)	$ (3)	$ (6)	$ (6)