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.

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Name:	us-gaap_Goodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Business Combinations - Prior Year Acquisitions (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020	Nov. 23, 2020	Sep. 30, 2020	Dec. 31, 2019	Jun. 01, 2017
Business Acquisition [Line Items]
Goodwill	$ 6,198,701	$ 6,252,636	$ 2,861		$ 1,328,045
TrademarkVision
Business Acquisition [Line Items]
Contingent stock liability		0
Kopernio
Business Acquisition [Line Items]
Contingent consideration				$ 2,184
Publons
Business Acquisition [Line Items]
Contingent stock liability		$ 0
Contingent consideration						$ 9,500