License Agreement - Additional Information (Details)	1 Months Ended
Jun. 30, 2015 USD ($)
License Agreement \| Amgen, Inc
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Maximum future payments upon achievement of certain development and commercial milestones	$ 172,500,000

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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