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Related-Party Transactions (Details) - USD ($)	12 Months Ended
Related-Party Transactions (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Relamorelin Company and/or Motus
Related Party Transaction
Net costs			$ 1,570,000
Accounts Payable
Related Party Transaction
Outstanding payments due to consultants	$ 260,000	$ 90,000
Consultant
Related Party Transaction
Expenses paid to consultants	$ 2,005,000	$ 2,400,000.000	$ 619,000