Acquisitions and Divestitures - Merger with 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
Business Acquisition [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 replacement equity awards \| $	$ 43,536
IHS Markit \| Common Stock $1 par
Business Acquisition [Line Items]
Fair value of S&P Global common stock and replacement equity awards \| $	$ 43,345
IHS Markit \| 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 S&P Global common stock and replacement equity awards \| $	$ 191
IHS Markit
Business Acquisition [Line Items]
Actual shares outstanding at period end (shares)	400,988,207
IHS Markit \| IHS Markit \| EBT
Business Acquisition [Line Items]
Actual shares outstanding at period end (shares)	25,219,470

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Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

+ References

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)
-URI https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479

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Number of shares of equity interests issued or issuable to acquire entity.

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