Condensed Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2020		146,083,110
Beginning balance at Dec. 31, 2020	$ 134,243	$ 146	$ 1,021,221	$ (1,829)	$ (885,295)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(35,697)				(35,697)
Other comprehensive income (loss), net	(1,678)			(1,678)
Recognition of stock-based compensation expense	4,212		4,212
Restricted stock award grants, net of forfeitures (in shares)		1,966,333
Restricted stock award grants, net of forfeitures	2	$ 2
Issuance of common shares (in shares)		5,678,893
Issuance of common shares	21,357	$ 6	21,351
Ending balance (in shares) at Mar. 31, 2021		153,728,336
Ending balance at Mar. 31, 2021	122,439	$ 154	1,046,784	(3,507)	(920,992)
Beginning balance (in shares) at Dec. 31, 2020		146,083,110
Beginning balance at Dec. 31, 2020	134,243	$ 146	1,021,221	(1,829)	(885,295)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(118,913)
Ending balance (in shares) at Sep. 30, 2021		163,957,900
Ending balance at Sep. 30, 2021	79,464	$ 164	1,086,989	(3,481)	(1,004,208)
Beginning balance (in shares) at Dec. 31, 2020		146,083,110
Beginning balance at Dec. 31, 2020	$ 134,243	$ 146	1,021,221	(1,829)	(885,295)
Ending balance (in shares) at Dec. 31, 2021	164,502,013	164,502,013
Ending balance at Dec. 31, 2021	$ 47,553	$ 165	1,094,353	(3,042)	(1,043,923)
Beginning balance (in shares) at Mar. 31, 2021		153,728,336
Beginning balance at Mar. 31, 2021	122,439	$ 154	1,046,784	(3,507)	(920,992)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(50,132)				(50,132)
Other comprehensive income (loss), net	180			180
Recognition of stock-based compensation expense	4,360		4,360
Issuance of common stock for employee stock purchase plan (in shares)		163,463
Issuance of common stock for employee stock purchase plan	474		474
Issuance of common stock upon exercise of stock options (in shares)		1,250
Issuance of common stock upon exercise of stock options	2		2
Restricted stock award grants, net of forfeitures (in shares)		39,127
Restricted stock award grants, net of forfeitures	0
Issuance of common shares (in shares)		10,172,498
Issuance of common shares	31,265	$ 10	31,255
Issuance of common stock upon vesting of restricted stock units (in shares)		1,386
Ending balance (in shares) at Jun. 30, 2021		164,106,060
Ending balance at Jun. 30, 2021	108,588	$ 164	1,082,875	(3,327)	(971,124)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(33,084)				(33,084)
Other comprehensive income (loss), net	(154)			(154)
Recognition of stock-based compensation expense	4,114		4,114
Restricted stock award grants, net of forfeitures (in shares)		(148,160)
Ending balance (in shares) at Sep. 30, 2021		163,957,900
Ending balance at Sep. 30, 2021	$ 79,464	$ 164	1,086,989	(3,481)	(1,004,208)
Beginning balance (in shares) at Dec. 31, 2021	164,502,013	164,502,013
Beginning balance at Dec. 31, 2021	$ 47,553	$ 165	1,094,353	(3,042)	(1,043,923)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(15,442)				(15,442)
Other comprehensive income (loss), net	134			134
Recognition of stock-based compensation expense	3,011		3,011
Restricted stock award grants, net of forfeitures (in shares)		1,675,472
Restricted stock award grants, net of forfeitures	0	$ 2	(2)
Issuance of common shares (in shares)		12,500,000
Issuance of common shares	20,000	$ 12	19,988
Issuance of common stock upon vesting of performance units (in shares)		150,000
Ending balance (in shares) at Mar. 31, 2022		178,827,485
Ending balance at Mar. 31, 2022	$ 55,256	$ 179	1,117,350	(2,908)	(1,059,365)
Beginning balance (in shares) at Dec. 31, 2021	164,502,013	164,502,013
Beginning balance at Dec. 31, 2021	$ 47,553	$ 165	1,094,353	(3,042)	(1,043,923)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ (66,415)
Issuance of common stock upon exercise of stock options (in shares)	0
Ending balance (in shares) at Sep. 30, 2022	203,339,656	203,339,656
Ending balance at Sep. 30, 2022	$ 35,852	$ 203	1,148,996	(3,009)	(1,110,338)
Beginning balance (in shares) at Mar. 31, 2022		178,827,485
Beginning balance at Mar. 31, 2022	55,256	$ 179	1,117,350	(2,908)	(1,059,365)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(29,048)				(29,048)
Other comprehensive income (loss), net	(47)			(47)
Recognition of stock-based compensation expense	2,077		2,077
Issuance of common stock for employee stock purchase plan (in shares)		388,541
Issuance of common stock for employee stock purchase plan	257		257
Restricted stock award grants, net of forfeitures (in shares)		34,420
Issuance of common shares (in shares)		5,619,827
Issuance of common shares	4,947	$ 6	4,941
Ending balance (in shares) at Jun. 30, 2022		184,870,273
Ending balance at Jun. 30, 2022	33,442	$ 185	1,124,625	(2,955)	(1,088,413)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(21,925)				(21,925)
Other comprehensive income (loss), net	(54)			(54)
Recognition of stock-based compensation expense	2,547		2,547
Restricted stock award grants, net of forfeitures (in shares)		(424,735)
Restricted stock award grants, net of forfeitures	(1)	$ (1)
Issuance of warrants upon debt financing	230		230
Issuance of common shares (in shares)		18,894,118
Issuance of common shares	$ 21,613	$ 19	21,594
Ending balance (in shares) at Sep. 30, 2022	203,339,656	203,339,656
Ending balance at Sep. 30, 2022	$ 35,852	$ 203	$ 1,148,996	$ (3,009)	$ (1,110,338)