Consolidated Statements of Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Revenue	$ 1,846	$ 1,689	$ 5,575	$ 4,964
Expenses:
Operating-related expenses	519	480	1,533	1,460
Selling and general expenses	339	318	944	992
Depreciation	20	20	60	61
Amortization of intangibles	32	29	94	92
Total expenses	910	847	2,631	2,605
Gain on dispositions	(8)	(49)	(16)	(49)
Operating profit	944	891	2,960	2,408
Other (income) expense, net	(6)	8	(16)	104
Interest expense, net	35	32	109	105
Loss on extinguishment of debt	279	0	279	0
Income before taxes on income	636	851	2,588	2,199
Provision for taxes on income	138	189	559	482
Net income	498	662	2,029	1,717
Less: net income attributable to noncontrolling interests	(43)	(45)	(144)	(135)
Net income attributable to S&P Global Inc.	$ 455	$ 617	$ 1,885	$ 1,582
Net income:
Basic (USD per share)	$ 1.89	$ 2.52	$ 7.82	$ 6.43
Diluted (USD per share)	$ 1.88	$ 2.50	$ 7.78	$ 6.40
Weighted-average number of common shares outstanding:
Basic (shares)	240.6	245.0	241.2	245.9
Diluted (shares)	241.6	246.5	242.3	247.4
Actual shares outstanding at period end (shares)	240.6	244.4	240.6	244.4