Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 498	$ 662	$ 2,029	$ 1,717
Other comprehensive income:
Foreign currency translation adjustments	(1)	(35)	(54)	(33)
Income tax effect	15	2	15	6
Foreign currency translation adjustment, net of income tax effect	14	(33)	(39)	(27)
Pension and other postretirement benefit plans	3	2	(30)	116
Income tax effect	(1)	0	8	(28)
Pension and other postretirement benefit plans, net of income tax effect	2	2	(22)	88
Unrealized gain (loss) on forward exchange contracts	14	(4)	10	(4)
Income tax effect	(3)	1	(2)	1
Unrealized gain on investment and forward exchange contracts, net of income tax effect	11	(3)	8	(3)
Comprehensive income	525	628	1,976	1,775
Less: comprehensive income attributable to nonredeemable noncontrolling interests	(3)	(1)	(8)	(7)
Less: comprehensive income attributable to redeemable noncontrolling interests	(40)	(44)	(136)	(128)
Comprehensive income attributable to S&P Global Inc.	$ 482	$ 583	$ 1,832	$ 1,640