SUBSEQUENT EVENT	12 Months Ended
Dec. 31, 2018
Subsequent Events [Abstract]
SUBSEQUENT EVENT	22. SUBSEQUENT EVENT On February 27, 2019, the Company announced that it exercised the exclusive option to acquire Myonexus as more fully described in Note 3, License and Collaboration Agreements. The final exercise price as negotiated between the Company and Myonexus was $165.0 million. The Company may also be required to make up to $200.0 million in additional payments to the selling shareholders of Myonexus based on the achievement of certain milestones. The Company has evaluated subsequent events from the date of the consolidated balance sheet through the date the consolidated financial statements were issued.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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