Related Party Transactions	12 Months Ended
Dec. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions	14. Related Party Transactions Casebia Prior to the termination of the joint venture, Casebia was a related party under ASC 850, Related Party Disclosures (“ASC 850”). Refer to Note 7, “Joint Venture with Bayer Healthcare LLC.” Vertex In the fourth quarter of 2018, upon becoming owners of record of more than 10% of the voting interest of the Company, Vertex became a related party under ASC 850. As of July 2, 2019, upon becoming owners of record of less than 10% of the voting interest of the Company, Vertex was no longer a related party under ASC 850. Refer to Note 7, “Agreements with Vertex Pharmaceuticals Incorporated and certain of its subsidiaries.”

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-URI http://asc.fasb.org/topic&trid=2122745

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