Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income/(Loss) [Member]	Accumulated Deficit [Member]	Total
Beginning Balance at Dec. 31, 2020	$ 610	$ 0	$ 825,794	$ (42)	$ (322,843)	$ 503,519
Beginning Balance (in shares) at Dec. 31, 2020	60,996,367
Issuance of common stock pursuant to exercise of stock options	$ 9	0	8,783	0	0	8,792
Issuance of common stock pursuant to exercise of stock options (in shares)	991,432
Unrealized comprehensive loss on investments	$ 0	0	0	(33)	0	(33)
Share-based compensation	0	0	7,900	0	0	7,900
Net loss	0	0	0	0	(40,179)	(40,179)
Ending Balance at Mar. 31, 2021	$ 619	0	842,477	(75)	(363,022)	479,999
Ending Balance (in shares) at Mar. 31, 2021	61,987,799
Beginning Balance at Dec. 31, 2021	$ 645	0	946,152	(161)	(491,912)	454,724
Beginning Balance (in shares) at Dec. 31, 2021	64,505,889
Issuance of common stock pursuant to exercise of stock options and restricted stock units	$ 0	0	76	0	0	76
Issuance of common stock pursuant to exercise of stock options and restricted stock units (in shares)	16,168
Unrealized comprehensive loss on investments	$ 0	0	0	(468)	0	(468)
Share-based compensation	0	0	6,270	0	0	6,270
Net loss	0	0	0	0	(42,982)	(42,982)
Ending Balance at Mar. 31, 2022	$ 645	$ 0	$ 952,498	$ (629)	$ (534,894)	$ 417,620
Ending Balance (in shares) at Mar. 31, 2022	64,522,057