Segment and Related Information - Operating Results by Segment (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Segment Reporting Information [Line Items]
Revenue	$ 2,993	$ 2,106	$ 5,383	$ 4,122
Operating Profit	1,482	1,154	3,374	2,234
Equity in income on unconsolidated subsidiaries	11	0	15	0
Gain on dispositions	556	0	1,899	2
Amortization of intangibles from acquisitions	267	22	379	53
Lease impairment	20		25
IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	135	50	379	99
Operating Segments
Segment Reporting Information [Line Items]
Operating Profit	1,636	1,240	4,037	2,407
Operating Segments \| Market Intelligence
Segment Reporting Information [Line Items]
Revenue	1,030	539	1,758	1,063
Operating Profit	702	174	2,191	335
Gain on dispositions	518		1,900	2
Employee severance charges	13		31
Acquisition-related costs	1		1
Amortization of intangibles from acquisitions	133	16	197	33
Operating Segments \| Market Intelligence \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	12		15
Operating Segments \| Ratings
Segment Reporting Information [Line Items]
Revenue	796	1,073	1,663	2,090
Operating Profit	464	729	976	1,410
Employee severance charges	7		12
Amortization of intangibles from acquisitions	2	2	3	7
Operating Segments \| Commodity Insights
Segment Reporting Information [Line Items]
Revenue	438	252	801	492
Operating Profit	141	141	299	275
Employee severance charges	17		24
Amortization of intangibles from acquisitions	32	2	45	4
Operating Segments \| Commodity Insights \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	4		6
Operating Segments \| Mobility
Segment Reporting Information [Line Items]
Revenue	337	0	452	0
Operating Profit	58	0	76	0
Employee severance charges	2		2
Acquisition-related costs	3		4
Amortization of intangibles from acquisitions	77		101
Operating Segments \| Mobility \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	1		1
Operating Segments \| Indices
Segment Reporting Information [Line Items]
Revenue	339	278	661	548
Operating Profit	270	196	493	387
Gain on dispositions	38		38
Employee severance charges	2		4
Amortization of intangibles from acquisitions	9	1	13	3
Operating Segments \| Indices \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	1		1
Operating Segments \| Engineering Solutions
Segment Reporting Information [Line Items]
Revenue	96	0	129	0
Operating Profit	1	0	2	0
Employee severance charges	1		2
Amortization of intangibles from acquisitions	15		19
Intersegment Elimination
Segment Reporting Information [Line Items]
Revenue	(43)	(36)	(81)	(71)
Corporate Unallocated
Segment Reporting Information [Line Items]
Operating Profit	(165)	(86)	(678)	(173)
Equity in income on unconsolidated subsidiaries	11	0	15	0
Employee severance charges	18		64
Acquisition-related costs	4		5
Asset write-offs	3		3
S&P Foundation grant			200
Lease impairment			5
Retention related expenses				2
Amortization of intangibles from acquisitions	14		28
Corporate Unallocated \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	$ 117	50	357	99
Amortization of intangibles from acquisitions			$ 1	7
Lease impairment		$ 3		$ 3

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