Acquisitions and Divestitures - Schedule of Estimated Fair Value of the Consideration Transferred for IHS Markit (Details) $ / shares in Units, $ in Millions	Feb. 28, 2022 USD ($) $ / shares shares
Business Acquisition [Line Items]
Closing price per share of S&P Global common stock (USD per share) | $ / shares	$ 380.89
IHS Markit Ltd
Business Acquisition [Line Items]
Number of shares IHS Markit issued and outstanding (shares)	400,988,207
Exchange ratio	28.38%
Number of S&P Global common stock transferred to IHS Markit stockholders (shares)	113,800,453
Fair value of the consideration transferred for IHS Markit | $	$ 43,536
IHS Markit Ltd | Common Stock
Business Acquisition [Line Items]
Fair value of the consideration transferred for IHS Markit | $	$ 43,345
IHS Markit Ltd | Replacement Equity Awards
Business Acquisition [Line Items]
Number of S&P Global common stock transferred to IHS Markit stockholders (shares)	900,000
Fair value of the consideration transferred for IHS Markit | $	$ 191
IHS Markit Ltd | IHS Markit Ltd | Trust for Benefit of Employees
Business Acquisition [Line Items]
Number of shares IHS Markit issued and outstanding (shares)	25,219,470