Subsequent Event	9 Months Ended
Sep. 30, 2023
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn October 31, 2023, the Company’s Board of Directors authorized incremental share repurchases of up to an additional $500.0 million of Gartner’s common stock. This authorization is in addition to the previously authorized repurchases of up to $4.2 billion, which, as of the end of October 2023, had approximately $500.0 million remaining.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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