Description of Business and Basis of Presentation (Details) $ in Thousands		3 Months Ended
	Mar. 15, 2018 USD ($)	Mar. 31, 2018 USD ($) drug product	Mar. 31, 2017 USD ($)
Debt Instrument [Line Items]
Number of commercial products | product		2
Number of orphan drugs | drug		1
Net income (loss)		$ 32,828	$ 30,962
Cash used to fund operating activities		$ 22,731	$ 24,834
Net proceeds from new loan, net of debt discount	$ 20,000