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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