Goodwill and Intangible Assets - Narrative (Detail) - USD ($) $ in Thousands		9 Months Ended
	Jun. 18, 2021	Sep. 30, 2021
Trapelo Health
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired		$ 44,664
Trapelo Health | Clinical Services
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired		44,664
Trapelo Health | Pharma Services
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired		0
Inivata
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired	$ 61,300	270,055
Inivata | Clinical Services
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired		237,251
Inivata | Pharma Services
Finite-Lived Intangible Assets [Line Items]
Goodwill acquired		$ 32,804