Goodwill and Intangible Assets - Rollforward of Goodwill (Details) - USD ($) $ in Thousands		6 Months Ended
	Jun. 18, 2021	Jun. 30, 2021
Goodwill [Roll Forward]
Goodwill, beginning balance		$ 211,083
Goodwill, ending balance		499,977
Trapelo Health
Goodwill [Roll Forward]
Goodwill acquired		44,664
Inivata
Goodwill [Roll Forward]
Goodwill acquired	$ 64,700	244,230
Goodwill, ending balance	244,230	244,200
Clinical Services
Goodwill [Roll Forward]
Goodwill, beginning balance		179,534
Goodwill, ending balance		438,761
Clinical Services | Trapelo Health
Goodwill [Roll Forward]
Goodwill acquired		44,664
Clinical Services | Inivata
Goodwill [Roll Forward]
Goodwill acquired		214,563
Goodwill, ending balance	214,500
Pharma Services
Goodwill [Roll Forward]
Goodwill, beginning balance		31,549
Goodwill, ending balance		61,216
Pharma Services | Trapelo Health
Goodwill [Roll Forward]
Goodwill acquired		0
Pharma Services | Inivata
Goodwill [Roll Forward]
Goodwill acquired		$ 29,667
Goodwill, ending balance	$ 29,700