Consolidated Statements of Equity - 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, 2015		$ 243	$ 194	$ 412	$ 475	$ 7,636		$ (600)		$ (7,729)	$ 49
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	[1]	1,946	1,933			2,106		(173)			13
Dividends		(390)	(380)			(380)					(10)
Share repurchases		(1,097)	(1,097)							1,097
Employee stock plans		152	152		27					(125)
Change in redemption value of redeemable noncontrolling interest		(153)	(153)			(153)
Other		0	1			1					(1)
Ending Balance at Dec. 31, 2016		701	650	412	502	9,210		(773)		(8,701)	51
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	[1]	1,635	1,620			1,496		124			15
Dividends		(431)	(421)			(421)					(10)
Share repurchases		(1,006)	(1,001)							1,001	(5)
Employee stock plans		131	123		23					(100)	8
Change in redemption value of redeemable noncontrolling interest		(260)	(260)			(260)
Other		(4)	(2)			(2)					(2)
Ending Balance at Dec. 31, 2017		766	709	412	525	10,023		(649)		(9,602)	57
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	[1]	1,867	1,855			1,958		(103)			12
Dividends		(514)	(503)			(503)					(11)
Share repurchases		(1,660)	(1,660)		(75)					1,585
Retirement of common stock		0		(118)						(118)
Employee stock plans		84	84		56					(28)
Change in redemption value of redeemable noncontrolling interest		(228)	(228)			(228)
Increase in CRISIL ownership		(23)	(25)		(25)						2
Stock consideration for Kensho		352	352		352
Other		40	44			34	[2]	10	[2]		(4)
Ending Balance at Dec. 31, 2018		$ 684	$ 628	$ 294	$ 833	$ 11,284		$ (742)		$ (11,041)	$ 56

[1] Excludes $151 million, $129 million and $109 million in 2018, 2017 and 2016, respectively, attributable to redeemable noncontrolling interest.

[2] Includes opening balance sheet adjustments related to the adoption of the new revenue recognition standard and the reclassification of the unrealized loss on investments from Accumulated other comprehensive loss to Retained income. See Note 1 — Accounting Policies for additional details.