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v3.23.1

Goodwill and Intangible Assets - Changes to the Carrying Amount of Goodwill by Segment (Details) - USD ($) | 3 Months Ended
--- | ---
Mar. 31, 2023 | Sep. 30, 2022
Goodwill [Line Items] |  |
Goodwill impairment |  | $ 0
Goodwill [Roll Forward] |  |
Beginning balance | $ 2,930,211,000 |
Foreign currency translation impact | (270,000) |
Ending balance | 2,929,941,000 |
Goodwill, accumulated impairment losses | 0 |
Research |  |
Goodwill [Roll Forward] |  |
Beginning balance | 2,651,193,000 |
Foreign currency translation impact | (390,000) |
Ending balance | 2,650,803,000 |
Conferences |  |
Goodwill [Roll Forward] |  |
Beginning balance | 183,951,000 |
Foreign currency translation impact | 1,000 |
Ending balance | 183,952,000 |
Consulting |  |
Goodwill [Roll Forward] |  |
Beginning balance | 95,067,000 |
Foreign currency translation impact | 119,000 |
Ending balance | $ 95,186,000 |

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