Consolidated Statements of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Revenue	$ 2,106	$ 1,943	$ 4,122	$ 3,729
Expenses:
Operating-related expenses	533	493	1,060	1,011
Selling and general expenses	374	295	735	609
Depreciation	23	19	42	39
Amortization of intangibles	22	32	53	61
Total expenses	952	839	1,890	1,720
Gain on dispositions	0	(1)	(2)	(8)
Operating profit	1,154	1,105	2,234	2,017
Other income, net	(22)	(10)	(29)	(9)
Interest expense, net	32	40	63	74
Income before taxes on income	1,144	1,075	2,200	1,952
Provision for taxes on income	287	233	534	421
Net income	857	842	1,666	1,531
Less: net income attributable to noncontrolling interests	$ (59)	(50)	(113)	(100)
Net income attributable to S&P Global Inc.		$ 792	$ 1,553	$ 1,431
Net income:
Basic (USD per share)	$ 3.31	$ 3.29	$ 6.45	$ 5.92
Diluted (USD per share)	$ 3.30	$ 3.28	$ 6.42	$ 5.90
Weighted-average number of common shares outstanding:
Basic (shares)	240.8	240.9	240.7	241.5
Diluted (shares)	241.8	241.9	241.7	242.6
Actual shares outstanding at period end (shares)	241.0	241.0	241.0	241.0