Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Series A Convertible Voting Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]
Stockholders Equity, Beginning Balance at Dec. 31, 2018	$ 94,479		$ 74	$ 771,817	$ (677,412)
Stockholders Equity, Beginning Balance, Shares at Dec. 31, 2018			1,859,120
Issuance of common stock for exercise of common stock options	445			445
Issuance of common stock for exercise of common stock options, Shares			8,056
Stock-based compensation	5,695			5,695
Issuance of convertible voting preferredstock, net of offering costs	74,001	$ 1		74,000
Issuance of convertible voting preferredstock, net of offering costs, Share		103,000
Net loss	(88,275)				(88,275)
Stockholders Equity, Ending Balance at Dec. 31, 2019	86,345	$ 1	$ 74	851,957	(765,687)
Stockholders Equity, Ending Balance, Shares at Dec. 31, 2019		103,000	1,867,176
Conversion of Series A convertible voting preferred stock to common stock		$ (1)	$ 8	(7)
Conversion of Series A convertible voting preferred stock to common stock, Shares		(103,000)	7,803,273
Reclassification of warrant liabilities to equity	62,175			62,175
Issuance of common stock in connection with an amendment to the asset purchase agreement	8,782		$ 1	8,781
Number of shares issued in connection with an amendment to asset purchase agreement			725,283
Issuance of warrant in connection with an amendment to the asset purchase agreement	3,188			3,188
Reverse stock split adjustment			$ (73)	73
Stock-based compensation	9,470			9,470
Issuance of common stock	8,901		$ 1	8,900
Issuance of common stock, Shares			732,752
Net loss	(80,902)				(80,902)
Stockholders Equity, Ending Balance at Dec. 31, 2020	97,959		$ 11	944,537	(846,589)
Stockholders Equity, Ending Balance, Shares at Dec. 31, 2020			11,128,484
Stockholders Equity, Beginning Balance at Dec. 31, 2019	86,345	$ 1	$ 74	851,957	(765,687)
Stockholders Equity, Beginning Balance, Shares at Dec. 31, 2019		103,000	1,867,176
Stockholders Equity, Ending Balance at Dec. 31, 2021	95,998		$ 16	1,037,230	(941,248)
Stockholders Equity, Ending Balance, Shares at Dec. 31, 2021			15,571,656
Stockholders Equity, Beginning Balance at Dec. 31, 2020	97,959		$ 11	944,537	(846,589)
Stockholders Equity, Beginning Balance, Shares at Dec. 31, 2020			11,128,484
Issuance of common stock for exercise of common stock options	847			847
Issuance of common stock for exercise of common stock options, Shares			64,847
Stock-based compensation	12,890			12,890
Issuance of common stock	78,151		$ 5	78,146
Issuance of common stock, Shares			4,316,968
Issuance of common stock for exercise of common stock warrants	810			810
Issuance of common stock for exercise of common stock warrant, Shares			61,357
Net loss	(94,659)				(94,659)
Stockholders Equity, Ending Balance at Dec. 31, 2021	$ 95,998		$ 16	$ 1,037,230	$ (941,248)
Stockholders Equity, Ending Balance, Shares at Dec. 31, 2021			15,571,656