Summary of Significant Accounting Policies Segment Information and Signficant Customers (Details) - segment	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Number of operating segments	1
Entity Wide Revenue Sanofi Percentage	89.00%	53.00%	65.00%
Biologics customer concentration		25.00%
LXRX Diplomat customer concentration		14.00%
Entity Wide Revenue Ipsen Percentage			18.00%

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

No definition available.

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Balance Type:	na
Period Type:	duration