Related Party Transactions (Details) - Pharmaron Beijing Co., Ltd. - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Related Party Transactions
Expenses recorded	$ 0.9	$ 2.2
Owed to related party	$ 0.2		$ 0.8

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

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