Segment and Related Information - Operating Results by Segment (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Revenue	$ 2,389	$ 2,016
Net (gain) loss from investments	3	0
Operating Profit	1,892	1,081
Pre-tax gain on sale	1,344	2
Amortization of intangibles from acquisitions	111	31
Subscription
Segment Reporting Information [Line Items]
Revenue	1,125	781
Non-subscription / Transaction
Segment Reporting Information [Line Items]
Revenue	512	595
Non-transaction
Segment Reporting Information [Line Items]
Revenue	425	400
Asset-linked fees
Segment Reporting Information [Line Items]
Revenue	218	183
Sales usage-based royalties
Segment Reporting Information [Line Items]
Revenue	69	57
IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	230	49
Operating Segments
Segment Reporting Information [Line Items]
Operating Profit	2,401	1,167
Operating Segments \| Market Intelligence
Segment Reporting Information [Line Items]
Revenue	727	524
Operating Profit	1,489	161
Pre-tax gain on sale	1,300	2
Employee severance charges	18
Acquisition-related costs	2
Amortization of intangibles from acquisitions	64	16
Operating Segments \| Market Intelligence \| Subscription
Segment Reporting Information [Line Items]
Revenue	659	512
Operating Segments \| Market Intelligence \| Non-subscription / Transaction
Segment Reporting Information [Line Items]
Revenue	28	12
Operating Segments \| Market Intelligence \| Non-transaction
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Market Intelligence \| Asset-linked fees
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Market Intelligence \| Sales usage-based royalties
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Ratings
Segment Reporting Information [Line Items]
Revenue	868	1,017
Operating Profit	511	681
Employee severance charges	5
Amortization of intangibles from acquisitions	2	5
Operating Segments \| Ratings \| Subscription
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Ratings \| Non-subscription / Transaction
Segment Reporting Information [Line Items]
Revenue	404	582
Operating Segments \| Ratings \| Non-transaction
Segment Reporting Information [Line Items]
Revenue	464	435
Operating Segments \| Ratings \| Asset-linked fees
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Ratings \| Sales usage-based royalties
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Commodity Insights
Segment Reporting Information [Line Items]
Revenue	363	240
Operating Profit	158	134
Employee severance charges	7
Acquisition-related costs	2
Amortization of intangibles from acquisitions	13	2
Operating Segments \| Commodity Insights \| Subscription
Segment Reporting Information [Line Items]
Revenue	296	223
Operating Segments \| Commodity Insights \| Non-subscription / Transaction
Segment Reporting Information [Line Items]
Revenue	48	1
Operating Segments \| Commodity Insights \| Non-transaction
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Commodity Insights \| Asset-linked fees
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Commodity Insights \| Sales usage-based royalties
Segment Reporting Information [Line Items]
Revenue	19	16
Operating Segments \| Mobility
Segment Reporting Information [Line Items]
Revenue	115	0
Operating Profit	18	0
Acquisition-related costs	1
Amortization of intangibles from acquisitions	24
Operating Segments \| Mobility \| Subscription
Segment Reporting Information [Line Items]
Revenue	86	0
Operating Segments \| Mobility \| Non-subscription / Transaction
Segment Reporting Information [Line Items]
Revenue	29	0
Operating Segments \| Mobility \| Non-transaction
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Mobility \| Asset-linked fees
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Mobility \| Sales usage-based royalties
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Indices
Segment Reporting Information [Line Items]
Revenue	322	270
Operating Profit	224	191
Employee severance charges	2
Amortization of intangibles from acquisitions	4	1
Operating Segments \| Indices \| Subscription
Segment Reporting Information [Line Items]
Revenue	54	46
Operating Segments \| Indices \| Non-subscription / Transaction
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Indices \| Non-transaction
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Indices \| Asset-linked fees
Segment Reporting Information [Line Items]
Revenue	218	183
Operating Segments \| Indices \| Sales usage-based royalties
Segment Reporting Information [Line Items]
Revenue	50	41
Operating Segments \| Engineering Solutions
Segment Reporting Information [Line Items]
Revenue	33	0
Operating Profit	1	0
Employee severance charges	1
Amortization of intangibles from acquisitions	4
Operating Segments \| Engineering Solutions \| Subscription
Segment Reporting Information [Line Items]
Revenue	30	0
Operating Segments \| Engineering Solutions \| Non-subscription / Transaction
Segment Reporting Information [Line Items]
Revenue	3	0
Operating Segments \| Engineering Solutions \| Non-transaction
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Engineering Solutions \| Asset-linked fees
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Engineering Solutions \| Sales usage-based royalties
Segment Reporting Information [Line Items]
Revenue	0	0
Intersegment Elimination
Segment Reporting Information [Line Items]
Revenue	(39)	(35)
Intersegment Elimination \| Subscription
Segment Reporting Information [Line Items]
Revenue	0	0
Intersegment Elimination \| Non-subscription / Transaction
Segment Reporting Information [Line Items]
Revenue	0	0
Intersegment Elimination \| Non-transaction
Segment Reporting Information [Line Items]
Revenue	(39)	(35)
Intersegment Elimination \| Asset-linked fees
Segment Reporting Information [Line Items]
Revenue	0	0
Intersegment Elimination \| Sales usage-based royalties
Segment Reporting Information [Line Items]
Revenue	0	0
Corporate Unallocated
Segment Reporting Information [Line Items]
Net (gain) loss from investments	3	0
Operating Profit	(512)	(86)
Employee severance charges	46
Acquisition-related costs	15
Amortization of intangibles from acquisitions	15	7
S&P Foundation grant	200
Retention related expenses		2
Amortization of intangibles from acquisitions	15
Corporate Unallocated \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	$ 230	$ 49

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