Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Amounts attributable to S&P Global Inc. common shareholders:
Net income	$ 1,090	$ 991
Basic weighted-average number of common shares outstanding (shares)	307,300,000	313,600,000
Effect of dilutive securities (shares)	400,000	400,000
Diluted weighted-average number of common shares outstanding (shares)	307,700,000	314,000,000.0
Net income:
Net income: Basic (USD per share)	$ 3.55	$ 3.16
Net income: Diluted (USD per share)	$ 3.54	$ 3.16
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)	700,000	900,000