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v3.22.4

Goodwill and Intangible Assets - Changes to the Carrying Amount of Goodwill by Segment (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Goodwill [Roll Forward] |  |
Beginning Balance | $ 2,951,317 | $ 2,945,547
Additions due to acquisition | 4,617 | 11,486
Foreign currency translation impact | (9,723) | (5,716)
Reclassified as held-for-sale | (16,000) |
Ending Balance | 2,930,211 | 2,951,317
Research |  |
Goodwill [Roll Forward] |  |
Beginning Balance | 2,670,934 | 2,664,732
Additions due to acquisition | 4,617 | 11,486
Foreign currency translation impact | (8,358) | (5,284)
Reclassified as held-for-sale | (16,000) |
Ending Balance | 2,651,193 | 2,670,934
Conferences |  |
Goodwill [Roll Forward] |  |
Beginning Balance | 184,021 | 184,091
Additions due to acquisition | 0 | 0
Foreign currency translation impact | (70) | (70)
Reclassified as held-for-sale | 0 |
Ending Balance | 183,951 | 184,021
Consulting |  |
Goodwill [Roll Forward] |  |
Beginning Balance | 96,362 | 96,724
Additions due to acquisition | 0 | 0
Foreign currency translation impact | (1,295) | (362)
Reclassified as held-for-sale | 0 |
Ending Balance | $ 95,067 | $ 96,362

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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(10)(1)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 55 -Paragraph 24 -URI https://asc.fasb.org/extlink&oid=122137925&loc=d3e14258-109268 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 852 -SubTopic 10 -Section 55 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(15)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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