Business Combinations (Policies)	9 Months Ended
Sep. 30, 2021
Business Combinations [Abstract]
Business Combinations Policy	Our acquisition of Kantar Health is being treated as a purchase in accordance with Accounting Standards Codification Topic ("ASC") 805, Business Combinations, which requires allocation of the purchase price to the estimated fair values of the assets acquired and liabilities assumed in the transaction.

Disclosure of accounting policy for completed business combinations (purchase method, acquisition method or combination of entities under common control). This accounting policy may include a general discussion of the purchase method or acquisition method of accounting (including for example, the treatment accorded contingent consideration, the identification of assets and liabilities, the purchase price allocation process, how the fair values of acquired assets and liabilities are determined) and the entity's specific application thereof. An entity that acquires another entity in a leveraged buyout transaction generally discloses the accounting policy followed by the acquiring entity in determining the basis used to value its interest in the acquired entity, and the rationale for that accounting policy.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 05
-Paragraph 4
-Subparagraph (a)-(d)
-URI http://asc.fasb.org/extlink&oid=6909625&loc=d3e227-128457

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