Acquisitions - Schedule of Provisional Information (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	6 Months Ended
	Jun. 18, 2021	Apr. 07, 2021	Apr. 30, 2021	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Plus: Cash paid at closing				$ 419,404	$ 37,000
Goodwill				499,977		$ 211,083
Trapelo Health
Business Acquisition [Line Items]
Shares of common stock issued as consideration (in shares)		597,712	597,712
Stock price per share on closing date (in dollars per share)		$ 48.81
Common stock issued for consideration		$ 29,174
Plus: Cash paid at closing		35,591
Purchase price		64,765
Cash		713
Other current assets		282
Other long-term assets		268
Total identifiable assets acquired		20,852
Current liabilities		(751)
Net identifiable assets acquired		20,101
Goodwill		44,664
Total purchase consideration		64,765
Inivata
Business Acquisition [Line Items]
Plus: Cash paid at closing	$ 398,594
Fair value of Line of Credit	15,000
Purchase price	413,594
Fair value of previously-held equity interest	62,919
Fair value of Purchase Option	58,537
Total fair value of business combination	535,050
Cash	14,068
Other current assets	5,366
Property and equipment	1,753
Other long-term assets	6,240
Total identifiable assets acquired	364,431
Current liabilities	(4,241)
Deferred income tax liabilities	(64,680)
Other long-term liabilities	(4,690)
Net identifiable assets acquired	290,820
Goodwill	244,230			$ 244,200
Total purchase consideration	535,050
Marketing Assets | Trapelo Health
Business Acquisition [Line Items]
Intangible assets		549
Identifiable intangible assets - developed technology | Trapelo Health
Business Acquisition [Line Items]
Intangible assets		$ 19,040
Identifiable intangible assets - developed technology | Inivata
Business Acquisition [Line Items]
Intangible assets	302,982
Trademarks | Inivata
Business Acquisition [Line Items]
Intangible assets	31,700
Trade Name | Inivata
Business Acquisition [Line Items]
Intangible assets	$ 2,322