Consolidated Statements of Equity (Deficit) (Unaudited) - USD ($) $ in Millions		Total	Total SPGI Equity	Common Stock $1 par	Additional Paid-in Capital	Retained Income	Accumulated Other Comprehensive Loss	Less: Treasury Stock	Noncontrolling Interests
Beginning Balance at Dec. 31, 2019		$ 536	$ 479	$ 294	$ 903	$ 12,205	$ (624)	$ (12,299)	$ 57
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	[1]	604	603			639	(36)		1
Dividends		(161)	(161)			(161)
Share repurchases		(1,153)	(1,153)		(120)			1,033
Employee stock plans		(26)	(26)		(29)			(3)
Change in redemption value of redeemable noncontrolling interest		11	11			11
Other		(5)	(3)			(3)			(2)
Ending Balance at Mar. 31, 2020		(194)	(250)	294	754	12,691	(660)	(13,329)	56
Beginning Balance at Dec. 31, 2020		571	509	294	946	13,367	(637)	(13,461)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	[1]	746	744			755	(11)		2
Dividends		(186)	(186)			(186)
Employee stock plans		(19)	(19)		(11)			8
Change in redemption value of redeemable noncontrolling interest		(16)	(16)			16
Other		2	0						(2)
Ending Balance at Mar. 31, 2021		$ 1,098	$ 1,032	$ 294	$ 935	$ 13,920	$ (648)	$ (13,469)	$ 66

[1] Excludes comprehensive income of $51 million and $49 million for the three months ended March 31, 2021 and 2020, respectively, attributable to our redeemable noncontrolling interest.