Segment and Geographic Information - Segment Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment information
Revenue	$ 8,297	$ 7,442	$ 6,699
Operating Profit	4,221	3,617	3,226
Pre-tax gain (loss) on dispositions	11	16	49
Lease-related costs	124	144
Amortization of intangibles	96	123	122
Acquisition-related costs	2
Lease impairment charges	31	120	11
Ratings
Segment information
Lease-related costs		5
Operating segments
Segment information
Operating Profit	4,647	3,936	3,438
Operating segments \| Ratings
Segment information
Revenue	4,097	3,606	3,106
Operating Profit	2,629	2,223	1,783
Pre-tax gain (loss) on dispositions	6
Severance charges	3	4	11
Recovery of lease-related costs	4
Technology-related impairment charge		11
Amortization of intangibles	10	7	2
Operating segments \| Market Intelligence
Segment information
Revenue	2,247	2,106	1,959
Operating Profit	703	589	566
Pre-tax gain (loss) on dispositions	3	12
Severance charges	3	27	6
Lease-related costs	1	3
Amortization of intangibles	65	76	75
Pre-tax gain (loss) on dispositions			22
Acquisition-related costs	2		4
Operating segments \| Platts
Segment information
Revenue	950	878	844
Operating Profit	517	458	457
Severance charges		11	1
Recovery of lease-related costs	2
Lease-related costs		2
Amortization of intangibles	8	9	12
Pre-tax gain (loss) on dispositions			27
Operating segments \| Indices
Segment information
Revenue	1,149	989	918
Operating Profit	798	666	632
Severance charges		5
Recovery of lease-related costs	1
Technology-related impairment charge		2
Lease-related costs		1
Amortization of intangibles	6	6	6
Lease impairment charges		4
Intersegment Elimination
Segment information
Revenue	(146)	(137)	(128)
Corporate Unallocated expense
Segment information
Operating Profit	(426)	(319)	(212)
Pre-tax gain (loss) on dispositions	2
Severance charges	13	19	7
Lease-related costs	4
Amortization of intangibles	7	26	28
Lease impairment charges	3	116	11
Gain related to an acquisition		1
Non-cash acquisition and disposition-related costs/adjustments	2	12	$ 21
Corporate Unallocated expense \| IHS Markit Ltd
Segment information
Acquisition-related costs	$ 249	$ 24

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