Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 857	$ 842	$ 1,666	$ 1,531
Other comprehensive income:
Foreign currency translation adjustments	38	(17)	13	(54)
Income tax effect	7	(4)	2	2
Foreign currency translation adjustment, net of income tax effect	45	(21)	15	(52)
Pension and other postretirement benefit plans	(1)	(37)	20	(34)
Income tax effect	0	10	(4)	9
Pension and other postretirement benefit plans, net of income tax effect	(1)	(27)	16	(25)
Unrealized (loss) gain on cash flow hedges	(216)	5	(214)	(4)
Income tax effect	56	(1)	56	1
Unrealized gain on investment and forward exchange contracts, net of income tax effect	(160)	4	(158)	(3)
Comprehensive income	741	798	1,539	1,451
Less: comprehensive income attributable to nonredeemable noncontrolling interests	(8)	(4)	(10)	(5)
Less: comprehensive income attributable to redeemable noncontrolling interests	(51)	(46)	(103)	(95)
Comprehensive income attributable to S&P Global Inc.	$ 682	$ 748	$ 1,426	$ 1,351