Segment and Related Information - Operating Results by Segment (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Revenue	$ 3,160	$ 2,389
Operating Profit	1,144	1,892
Equity in Income on Unconsolidated Subsidiaries	14	3
Gain (loss) on dispositions	50	1,344
Amortization of intangibles from acquisitions	262	111
Lease impairment	6	5
Recurring variable revenue
Segment Reporting Information [Line Items]
Revenue	125	40
Operating Segments
Segment Reporting Information [Line Items]
Operating Profit	1,209	2,401
Operating Segments \| Market Intelligence
Segment Reporting Information [Line Items]
Revenue	1,071	727
Operating Profit	229	1,489
Gain (loss) on dispositions	46	1,300
Acquisition-related costs		2
Employee severance charges	6	18
Amortization of intangibles from acquisitions	141	64
Operating Segments \| Market Intelligence \| Recurring variable revenue
Segment Reporting Information [Line Items]
Revenue	125	40
Operating Segments \| Market Intelligence \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	13
Operating Segments \| Ratings
Segment Reporting Information [Line Items]
Revenue	824	868
Operating Profit	477	511
Employee severance charges	1	5
Amortization of intangibles from acquisitions	2	2
Operating Segments \| Ratings \| Recurring variable revenue
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Commodity Insights
Segment Reporting Information [Line Items]
Revenue	508	363
Operating Profit	187	158
Acquisition-related costs		2
Employee severance charges	2	7
Amortization of intangibles from acquisitions	33	13
Operating Segments \| Commodity Insights \| Recurring variable revenue
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Commodity Insights \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	13
Operating Segments \| Mobility
Segment Reporting Information [Line Items]
Revenue	358	115
Operating Profit	64	18
Acquisition-related costs	1	1
Amortization of intangibles from acquisitions	74	24
Operating Segments \| Mobility \| Recurring variable revenue
Segment Reporting Information [Line Items]
Revenue	0
Operating Segments \| Mobility \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	1
Operating Segments \| Indices
Segment Reporting Information [Line Items]
Revenue	341	322
Operating Profit	238	224
Gain (loss) on dispositions	4
Employee severance charges	1	2
Amortization of intangibles from acquisitions	9	4
Operating Segments \| Indices \| Recurring variable revenue
Segment Reporting Information [Line Items]
Revenue	0	0
Operating Segments \| Indices \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	1
Operating Segments \| Engineering Solutions
Segment Reporting Information [Line Items]
Revenue	100	33
Operating Profit	14	1
Employee severance charges		1
Amortization of intangibles from acquisitions	2	4
Operating Segments \| Engineering Solutions \| Recurring variable revenue
Segment Reporting Information [Line Items]
Revenue	0
Intersegment Elimination
Segment Reporting Information [Line Items]
Revenue	(42)	(39)
Intersegment Elimination \| Recurring variable revenue
Segment Reporting Information [Line Items]
Revenue		0
Corporate Unallocated
Segment Reporting Information [Line Items]
Operating Profit	(79)	(512)
Equity in Income on Unconsolidated Subsidiaries	14	3
Acquisition-related costs	1	11
Employee severance charges	1	46
Retention related expenses	13
S&P foundation grant		200
Lease impairment		5
Amortization of intangibles from acquisitions	14	14
Corporate Unallocated \| IHS Markit
Segment Reporting Information [Line Items]
Acquisition-related costs	37	$ 230
Amortization of intangibles from acquisitions	$ 1

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