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v3.23.3

Goodwill and Intangible Assets - Changes to the Carrying Amount of Goodwill by Segment (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 USD ($) | Sep. 30, 2023 USD ($)
Goodwill [Line Items] |  |
Goodwill impairment | $ 0 |
Goodwill [Roll Forward] |  |
Beginning balance |  | $ 2,930,211,000
Additions due to an acquisition |  | 4,176,000
Foreign currency translation impact |  | (1,121,000)
Ending balance | 2,933,266,000 | 2,933,266,000
Goodwill, accumulated impairment losses | 0 | 0
Research |  |
Goodwill [Roll Forward] |  |
Beginning balance |  | 2,651,193,000
Additions due to an acquisition |  | 4,176,000
Foreign currency translation impact |  | (1,267,000)
Ending balance | 2,654,102,000 | 2,654,102,000
Conferences |  |
Goodwill [Roll Forward] |  |
Beginning balance |  | 183,951,000
Additions due to an acquisition |  | 0
Foreign currency translation impact |  | 0
Ending balance | 183,951,000 | 183,951,000
Consulting |  |
Goodwill [Roll Forward] |  |
Beginning balance |  | 95,067,000
Additions due to an acquisition |  | 0
Foreign currency translation impact |  | 146,000
Ending balance | $ 95,213,000 | $ 95,213,000

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