CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
CONSOLIDATED BALANCE SHEETS
Current portion of deferred financing costs	$ 0	$ 7
Interest rate (as a percent)	4.50%	4.50%
Sale of future royalties, current portion and deferred financing costs	$ 206	$ 319
Sale of future royalties, noncurrent portion and deferred financing costs	$ 427	$ 584
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized shares	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares	300,000,000	300,000,000
Common stock, issued shares	202,443,000	194,998,000
Common stock, outstanding shares	202,443,000	194,998,000