Earnings Per Share - (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Amounts attributable to S&P Global Inc. common shareholders:
Net income	$ 991	$ 795
Basic weighted-average number of common shares outstanding (shares)	313,600,000	321,300,000
Effect of stock options and other dilutive securities (shares)	400,000	800,000
Diluted weighted-average number of common shares outstanding (shares)	314,000,000.0	322,100,000
Net income: Basic (USD per share)	$ 3.16	$ 2.47
Net income: Diluted (USD per share)	$ 3.16	$ 2.47
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from computation of diluted earnings (shares)	0	0
Restricted Stock and Unit Awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive shares excluded from computation of diluted earnings (shares)	900,000	800,000