UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' (DEFICIT) EQUITY - USD ($)	Total	Common stock	Additional Paid-in Capital	Contingently Issuable Common Stock	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning balances (in shares) at Dec. 31, 2020		48,943,082
Beginning balances at Dec. 31, 2020	$ 120,785,000	$ 5,000	$ 395,491,000	$ 17,600,000	$ 0	$ (292,311,000)
Increase (decrease) in stockholders' equity [Roll Forward]
Stock-based compensation	10,085,000		10,085,000
Release of Block B Sponsor Earnout Shares from restriction (in shares)		859,000
Issuance of contingently issuable common stock (in shares)		1,999,185
Issuance of Contingently Issuable Common Stock			17,600,000	(17,600,000)
Exercise of stock options (in shares)		123,837
Exercise of stock options	1,074,000		1,074,000
Exercise of warrants (in shares)		1,747,746
Exercise of warrants	20,099,000		20,099,000
Release of restricted stock units (in shares)		25,990
Cancellation of shares used to settle payroll tax withholding	0
Foreign currency translation adjustment	0
Net loss	(93,623,000)					(93,623,000)
Ending balances (in shares) at Sep. 30, 2021		53,698,840
Ending balances at Sep. 30, 2021	58,420,000	$ 5,000	444,349,000	0	0	(385,934,000)
Beginning balances (in shares) at Jun. 30, 2021		53,353,858
Beginning balances at Jun. 30, 2021	68,567,000	$ 5,000	436,372,000	0	0	(367,810,000)
Increase (decrease) in stockholders' equity [Roll Forward]
Stock-based compensation	4,412,000		4,412,000
Exercise of stock options (in shares)		36,660
Exercise of stock options	318,000		318,000
Exercise of warrants (in shares)		282,332
Exercise of warrants	3,247,000		3,247,000
Release of restricted stock units (in shares)		25,990
Cancellation of shares used to settle payroll tax withholding	0
Foreign currency translation adjustment	0
Net loss	(18,124,000)					(18,124,000)
Ending balances (in shares) at Sep. 30, 2021		53,698,840
Ending balances at Sep. 30, 2021	$ 58,420,000	$ 5,000	444,349,000	0	0	(385,934,000)
Beginning balances (in shares) at Dec. 31, 2021	53,786,632	53,786,632
Beginning balances at Dec. 31, 2021	$ 32,447,000	$ 5,000	448,969,000	0	0	(416,527,000)
Increase (decrease) in stockholders' equity [Roll Forward]
Stock-based compensation	10,993,000		10,993,000
Exercise of warrants (in shares)		600
Exercise of warrants	7,000		7,000
Release of restricted stock units (in shares)		567,453
Cancellation of shares used to settle payroll tax withholding (in shares)		(166,690)
Cancellation of shares used to settle payroll tax withholding	(929,000)		(929,000)
Issuance of common stock under conversion of Yorkville Note (in shares)		3,393,663
Issuance of common stock under conversion of Yorkville Note	7,535,000	$ 1,000	7,534,000
Issuance of common stock under ATM offering (in shares)		12,067,575
Issuance of common stock under ATM program	29,139,000	$ 1,000	29,138,000
Issuance of common stock under SEPA (in shares)		3,967,939
Issuance of common stock under SEPA	4,604,000	$ 1,000	4,603,000
Commitment fee for SEPA settled by common stock (in shares)		465,117
Commitment fee for SEPA settled by common stock	1,061,000		1,061,000
Foreign currency translation adjustment	4,000				4,000
Net loss	$ (173,200,000)					(173,200,000)
Ending balances (in shares) at Sep. 30, 2022	74,082,289	74,082,289
Ending balances at Sep. 30, 2022	$ (88,339,000)	$ 8,000	501,376,000	0	4,000	(589,727,000)
Beginning balances (in shares) at Jun. 30, 2022		58,519,739
Beginning balances at Jun. 30, 2022	(57,829,000)	$ 6,000	461,165,000	0	5,000	(519,005,000)
Increase (decrease) in stockholders' equity [Roll Forward]
Stock-based compensation	3,616,000		3,616,000
Exercise of warrants (in shares)		0
Release of restricted stock units (in shares)		139,846
Cancellation of shares used to settle payroll tax withholding (in shares)		(38,534)
Cancellation of shares used to settle payroll tax withholding	(77,000)		(77,000)
Issuance of common stock under conversion of Yorkville Note (in shares)		3,393,663
Issuance of common stock under conversion of Yorkville Note	7,535,000	$ 1,000	7,534,000
Issuance of common stock under ATM offering (in shares)		12,067,575
Issuance of common stock under ATM program	29,139,000	$ 1,000	29,138,000
Foreign currency translation adjustment	(1,000)				(1,000)
Net loss	$ (70,722,000)					(70,722,000)
Ending balances (in shares) at Sep. 30, 2022	74,082,289	74,082,289
Ending balances at Sep. 30, 2022	$ (88,339,000)	$ 8,000	$ 501,376,000	$ 0	$ 4,000	$ (589,727,000)