SUBSEQUENT EVENT	12 Months Ended
Dec. 31, 2019
Subsequent Events [Abstract]
SUBSEQUENT EVENT	22. SUBSEQUENT EVENT On February 14, 2020, the Company entered into an agreement to sell the rare pediatric disease PRV it received from the FDA in connection with the approval of VYONDYS 53 for consideration of $111.0 million. The closing of the transaction is subject to the expiration or termination of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 and other customary conditions. When the transaction closes, the net proceeds will be recorded as a gain from sale of the PRV as it does not have a carrying value at the time of the sale. 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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