Segment and Related Information - Schedule of Operating Results by Segment (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Segment Reporting Information [Line Items]
Revenue	$ 3,101	$ 2,993	$ 6,261	$ 5,383
Operating Profit	911	1,482	2,056	3,374
Equity in Income on Unconsolidated Subsidiaries	11	11	25	15
Gain (loss) on dispositions	(119)	556	(69)	1,899
Amortization of intangibles from acquisitions	261	267	522	379
Lease impairment	5	20	11	25
Operating Segments
Segment Reporting Information [Line Items]
Operating Profit	1,116	1,636	2,325	4,037
Operating Segments \| Market Intelligence
Segment Reporting Information [Line Items]
Revenue	1,079	1,030	2,150	1,758
Operating Profit	176	702	404	2,191
Gain (loss) on dispositions		518	46	1,900
Acquisition-related costs		1		1
Employee severance charges	16	13	22	31
Amortization of intangibles from acquisitions	140	133	281	197
Operating Segments \| Market Intelligence \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	12	12	25	15
Asset impairments and write-offs	5		5
Operating Segments \| Ratings
Segment Reporting Information [Line Items]
Revenue	851	796	1,675	1,663
Operating Profit	486	464	962	976
Employee severance charges	4	7	5	12
Amortization of intangibles from acquisitions	2	2	4	3
Operating Segments \| Commodity Insights
Segment Reporting Information [Line Items]
Revenue	462	438	970	801
Operating Profit	156	141	343	299
Employee severance charges	14	17	15	24
Amortization of intangibles from acquisitions	33	32	66	45
Operating Segments \| Commodity Insights \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	8	4	20	6
Operating Segments \| Mobility
Segment Reporting Information [Line Items]
Revenue	369	337	727	452
Operating Profit	68	58	133	76
Acquisition-related costs	1	3	1	4
Employee severance charges	3	2	4	2
Amortization of intangibles from acquisitions	76	77	150	101
Operating Segments \| Mobility \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs		1	1	1
Operating Segments \| Indices
Segment Reporting Information [Line Items]
Revenue	348	339	689	661
Operating Profit	226	270	464	493
Gain (loss) on dispositions		38	4	38
Employee severance charges	2	2	3	4
Amortization of intangibles from acquisitions	9	9	18	13
Operating Segments \| Indices \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	1	1	2	1
Operating Segments \| Engineering Solutions
Segment Reporting Information [Line Items]
Revenue	33	96	133	129
Operating Profit	4	1	19	2
Employee severance charges		1		2
Amortization of intangibles from acquisitions		15	1	19
Intersegment Elimination
Segment Reporting Information [Line Items]
Revenue	(41)	(43)	(83)	(81)
Corporate Unallocated
Segment Reporting Information [Line Items]
Operating Profit	(216)	(165)	(294)	(678)
Equity in Income on Unconsolidated Subsidiaries	11	11	25	15
Gain (loss) on dispositions	(120)		(120)
Acquisition-related costs	1	4	2	5
Employee severance charges	12	18	14	64
Amortization of intangibles from acquisitions	1		2	1
Retention related expenses	3		16
Asset write-off		3		3
S&P foundation grant				200
Lease impairment	15		15	5
Amortization of intangibles from acquisitions	14	14	28	28
Corporate Unallocated \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	$ 30	$ 117	$ 66	$ 357

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