Acquisitions (Notes)	3 Months Ended
Mar. 31, 2021
Business Combinations [Abstract]
Acquisitions	In 2020, the Company acquired four consulting services businesses for $186.0 million in aggregate purchase consideration. None of these acquisitions were material individually or in the aggregate. At March 31, 2021, the Company had not finalized the determination of fair values allocated to all of the assets and liabilities for certain of these acquisitions.

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-URI http://asc.fasb.org/topic&trid=2303972

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