Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 861	$ 498	$ 2,527	$ 2,029
Other comprehensive income:
Foreign currency translation adjustments	(7)	(1)	6	(54)
Income tax effect	(6)	15	(4)	15
Foreign currency translation adjustment, net of income tax effect	(13)	14	2	(39)
Pension and other postretirement benefit plans	5	3	25	(30)
Income tax effect	(1)	(1)	(5)	8
Pension and other postretirement benefit plans, net of income tax effect	4	2	20	(22)
Unrealized gain (loss) on cash flow hedges	31	14	(183)	10
Income tax effect	(8)	(3)	48	(2)
Unrealized gain on investment and forward exchange contracts, net of income tax effect	23	11	(135)	8
Comprehensive income	875	525	2,414	1,976
Less: comprehensive income attributable to nonredeemable noncontrolling interests	(6)	(3)	(17)	(8)
Less: comprehensive income attributable to redeemable noncontrolling interests	(58)	(40)	(161)	(136)
Comprehensive income attributable to S&P Global Inc.	$ 811	$ 482	$ 2,236	$ 1,832