Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Total revenues, net	$ 29,835	$ 22,970
Costs and expenses:
Cost of goods sold	6,780	6,700
Selling, general and administrative	31,524	32,598
Research and development	25,174	17,891
Total costs and expenses	63,478	57,189
Loss from operations	(33,643)	(34,219)
Other expense, net	(1,555)	(7,714)
Loss before income taxes	(35,198)	(41,933)
Income tax expense	693	31
Net loss	$ (35,891)	$ (41,964)
Net loss per common share—basic (in dollars per share)	$ (0.76)	$ (0.91)
Net loss per common share—diluted (in dollars per share)	$ (0.76)	$ (0.91)
Weighted average number of common shares outstanding—basic (in shares)	47,520,045	46,109,080
Weighted average number of common shares outstanding—diluted (in shares)	47,520,045	46,109,080
Net loss	$ (35,891)	$ (41,964)
Unrealized loss on available-for-sale investments, net	(304)	(12)
Comprehensive loss	$ (36,195)	$ (41,976)
Revenue from Contract with Customer, Product and Service [Extensible Enumeration]	Product [Member]