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v3.23.1

Segment Information - Information About Reportable Segments (Details) | 3 Months Ended
--- | ---
Mar. 31, 2023 USD ($) segment | Mar. 31, 2022 USD ($)
Segment Reporting Information [Line Items] |  |
Number of reportable segments | segment | 3 |
Operating income | $ 407,957,000 | $ 217,247,000
Intersegment Eliminations |  |
Segment Reporting Information [Line Items] |  |
Revenues | 0 |
Operating Segments |  |
Segment Reporting Information [Line Items] |  |
Revenues | 1,408,869,000 | 1,262,740,000
Operating income | 977,110,000 | 897,515,000
Operating Segments | Research |  |
Segment Reporting Information [Line Items] |  |
Revenues | 1,217,191,000 | 1,136,380,000
Operating income | 899,514,000 | 849,379,000
Operating Segments | Conferences |  |
Segment Reporting Information [Line Items] |  |
Revenues | 64,642,000 | 10,354,000
Operating income | 26,788,000 | (2,876,000)
Operating Segments | Consulting |  |
Segment Reporting Information [Line Items] |  |
Revenues | 127,036,000 | 116,006,000
Operating income | 50,808,000 | 51,012,000
Corporate and Reconciling Items |  |
Segment Reporting Information [Line Items] |  |
Operating income | $ (569,153,000) | $ (680,268,000)

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