Summary of Significant Accounting Policies Segment Information and Signficant Customers (Details)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue, Major Customer
Entity Wide Revenue Sanofi Percentage	90.00%	98.00%
Entity Wide Revenue Ipsen Percentage	9.00%		94.00%

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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