Related Party Transactions - (Details) - Investor - USD ($)	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Related Party Transactions
Related party expense, external research and preclinical development services	$ 733,000	$ 1,450,000
Related party expense, operating lease rent	$ 0	$ 244,000

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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