Entity Wide Disclosures - Summary of Revenue by Major Source (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation Of Revenue [Line Items]
Total revenue	$ 259,965	$ 230,879
Oncology
Disaggregation Of Revenue [Line Items]
Total revenue	79,138	69,212
Other
Disaggregation Of Revenue [Line Items]
Total revenue	68,938	50,569
Metabolic
Disaggregation Of Revenue [Line Items]
Total revenue	32,495	36,075
AVAI
Disaggregation Of Revenue [Line Items]
Total revenue	30,820	25,147
Central Nervous System
Disaggregation Of Revenue [Line Items]
Total revenue	24,812	23,977
Cardiology
Disaggregation Of Revenue [Line Items]
Total revenue	23,762	25,899
Revenue Net
Disaggregation Of Revenue [Line Items]
Total revenue	$ 259,965	$ 230,879