Related Party Transactions (Details) - Pharmaron Beijing Co., Ltd. - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Related Party Transactions
Expenses recorded	$ 500,000	$ 1,900,000	$ 1,400,000	$ 4,200,000
Owed to related party	$ 0		$ 0		$ 800,000

Carrying amount as of the balance sheet date of obligations due all related parties.

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