Subsequent Event	12 Months Ended
Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Event	SUBSEQUENT EVENTIn January 2020, the Company completed the sale of worldwide rights to Firdapse, the Company's commercial product for the treatment of Lambert-Eaton myasthenic syndrome, to a third party in exchange for a one-time payment of $67.0 million. Under the terms of the agreement, the Company agreed to provide certain services to the third-party purchaser, such as customer sales and support, for up to 12 months after the closing of the transaction.

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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