Consolidated Statements of Equity (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		1,356		1,351				1,431	(80)		5
Dividends		(325)		(323)				(323)			(2)
Share repurchase		1,153		1,153			120			(1,033)
Employee stock plans		(20)		(20)			(21)			(1)
Change in redemption value of redeemable noncontrolling interest		(124)		(124)				(124)
Other		(2)									(2)
Ending Balance at Jun. 30, 2020		268		210		294	762	13,189	(704)	(13,331)	58
Beginning Balance at Mar. 31, 2020		(194)		(250)		294	754	12,691	(660)	(13,329)	56
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	[1]	752		748				792	(44)		4
Dividends		(164)		(162)				(162)			(2)
Employee stock plans		6		6			8			2
Change in redemption value of redeemable noncontrolling interest		(135)		(135)				(135)
Other		3		3				3
Ending Balance at Jun. 30, 2020		268		210		294	762	13,189	(704)	(13,331)	58
Beginning Balance at Dec. 31, 2020		571		509		294	946	13,367	(637)	(13,461)	62
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income		1,436		1,426				1,553	(127)		10
Dividends		(378)		(371)				(371)			(7)
Employee stock plans		13		13			17			4
Change in redemption value of redeemable noncontrolling interest		(312)		(312)				(312)
Other		1									1
Ending Balance at Jun. 30, 2021		1,331		1,265		294	963	14,237	(764)	(13,465)	66
Beginning Balance at Mar. 31, 2021		1,098		1,032		294	935	13,920	(648)	(13,469)	66
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income		690	[1]	682	[1]			798	(116)		8
Dividends		(192)		(185)				(185)			(7)
Employee stock plans		32		32			28			(4)
Change in redemption value of redeemable noncontrolling interest		(296)		(296)				(296)
Other		(1)		0							(1)
Ending Balance at Jun. 30, 2021		$ 1,331		$ 1,265		$ 294	$ 963	$ 14,237	$ (764)	$ (13,465)	$ 66

[1] Excludes comprehensive income of $51 million and $46 million three months ended June 30, 2021 and 2020, respectively, and $103 million and $95 million for the six months ended June 30, 2021 and 2020, respectively, attributable to our redeemable noncontrolling interest.