Business Combination, Acquisition and Integration Related Costs

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Business Combination, Deferred Consideration

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Business Combination, Future Compensation Expense

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Business Combination, Recognition of Compensation Expense, Term

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite Lived Intangible Assets And Goodwill

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of other liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Amount classified as deferred revenue attributable to disposal group held for sale or disposed of.

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Amount classified as goodwill attributable to disposal group held for sale or disposed of.

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Amount classified as intangible assets, excluding goodwill, attributable to disposal group held for sale or disposed of.

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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Amount of cash outflow, made soon after acquisition date of business combination, to settle contingent consideration liability.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Acquisitions and Divestiture (Details) - USD ($) $ in Thousands	1 Months Ended			12 Months Ended
	Sep. 30, 2023	Oct. 31, 2022	Jun. 30, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Feb. 28, 2023	Jun. 17, 2021
Business Acquisition [Line Items]
Cash paid for acquisition net of cash acquired				$ 3,800	$ 9,508	$ 22,939
Payment for contingent consideration liability, investing activities					4,100
Gain from sale of divested operation				135,410	0	0
Acquisition and integration charges				9,587	$ 9,079	6,055
Deferred consideration						2,300
TalentNeuron
Business Acquisition [Line Items]
Gain from sale of divested operation				135,400
TalentNeuron
Business Acquisition [Line Items]
Sale of business, consideration							$ 161,100
Goodwill				16,000
Intangible assets, net				9,500
Property, equipment and leasehold improvements, net,				4,500
Accounts receivable				11,800
Deferred revenue				24,400
Gartner Research Products
Business Acquisition [Line Items]
Percent of outstanding membership interests acquired	100.00%
Purchase price	$ 7,900
Chicago, Illinois
Business Acquisition [Line Items]
Percent of outstanding membership interests acquired		100.00%
Purchase price		$ 6,400
Pulse Q&A Inc.
Business Acquisition [Line Items]
Percent of outstanding membership interests acquired			100.00%
Purchase price			$ 29,900
Cash paid for acquisition net of cash acquired						$ 22,900
Future compensation expense				$ 4,500
Business combination, recognition of compensation expense, term				3 years
Acquired finite lived intangible assets and goodwill								$ 31,000
Acquired other liabilities								$ 1,100