v3.19.3.a.u2

Related Party Transactions - Narrative (Details) - USD ($)	1 Months Ended		12 Months Ended
	Feb. 28, 2018	Feb. 15, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Accounts receivable			$ 337,000	$ 899,000
Affiliated Entity | Covington
Related Party Transaction [Line Items]
Legal services			100,000	200,000	$ 200,000
Outstanding accounts payable balances			0	0
Equity Method Investee | AstraZeneca
Related Party Transaction [Line Items]
Payments received			7,900,000	34,000,000	$ 1,100,000
Accounts receivable			$ 300,000	$ 900,000
Series G Redeemable Convertible Preferred Stock
Related Party Transaction [Line Items]
Shares of stock issued (in shares)	55,666,004	55,666,004
Price per share (usd per share)	$ 10.06	$ 10.06
Aggregate purchase price	$ 560,000,000	$ 560,000,000

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