Acquisitions and Divestitures - Merger with IHS Markit (Details) $ / shares in Units, $ in Millions	Feb. 28, 2022 USD ($) $ / shares shares
Asset Acquisition, Contingent Consideration [Line Items]
Closing price per share of S&P Global common stock (USD per share) \| $ / shares	$ 380.89
IHS Markit
Asset Acquisition, Contingent Consideration [Line Items]
Number of shares IHS Markit issued and outstanding (shares)	400,988,207
IHS Markit
Asset Acquisition, Contingent Consideration [Line Items]
Exchange ratio	28.38%
Number of S&P Global common stock transferred to IHS Markit stockholders (shares)	113,800,453
Fair value of S&P Global common stock and equity awards \| $	$ 43,536
IHS Markit \| Common Stock
Asset Acquisition, Contingent Consideration [Line Items]
Fair value of S&P Global common stock and equity awards \| $	$ 43,345
IHS Markit \| Replacement Equity Awards
Asset Acquisition, Contingent Consideration [Line Items]
Number of S&P Global common stock transferred to IHS Markit stockholders (shares)	900,000
Fair value of S&P Global common stock and equity awards \| $	$ 191
IHS Markit \| IHS Markit \| EBT
Asset Acquisition, Contingent Consideration [Line Items]
Number of shares IHS Markit issued and outstanding (shares)	25,219,470

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
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