Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating Expenses [Abstract]
Research and development	$ 72,017	$ 61,058	$ 50,647
Selling, general and administrative	35,505	27,020	24,702
Goodwill impairment	0	0	9,758
Gain on sale of nonfinancial assets	0	(509)	0
Total operating expenses	107,522	87,569	85,107
Loss from operations	(107,522)	(87,569)	(85,107)
Nonoperating Income (Expense) [Abstract]
Interest income	4,582	219	10
Interest expense	(5,777)	(3,993)	(3,642)
Change in fair value of warrant and derivative liabilities	7,074	1,701	(366)
Other income (expense)	554	(4,197)	426
Total other income (expense), net	6,433	(6,270)	(3,572)
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	(101,089)	(93,839)	(88,679)
Income Tax Expense (Benefit)	78	28	17
Net loss and comprehensive loss	(101,167)	(93,867)	(88,696)
Temporary Equity Repurchase Of Convertible Preferred Stock	0	(2,546)	(13,943)
Net loss attributable to common stockholders	$ (101,167)	$ (96,413)	$ (102,639)
Net loss per share attributable to common stockholders - basic (in dollars per share)	$ (0.57)	$ (1.52)	$ (3.99)
Net loss per share attributable to common stockholders - diluted (in dollars per share)	$ (0.57)	$ (1.52)	$ (3.99)
Weighted average shares of common stock outstanding - basic (in shares)	177,812,480	63,525,845	25,748,797
Weighted average shares of common stock outstanding - diluted (in shares)	177,812,480	63,525,845	25,748,797