CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net sales	$ 12,059,000	$ 12,752,000	$ 11,782,000
Cost of sales:
Cost of sales of products and services	8,325,000	9,449,000	7,663,000
Inventory write-down	1,184,000	0	4,500,000
Total cost of sales	9,509,000	9,449,000	12,163,000
Gross profit (loss)	2,550,000	3,303,000	(381,000)
Costs and expenses:
Research and development	25,353,000	26,915,000	21,943,000
Sales, general and administrative	31,225,000	39,193,000	49,236,000
Total costs and expenses	56,578,000	66,108,000	71,179,000
Loss from operations	(54,028,000)	(62,805,000)	(71,560,000)
Other (expense) income:
Gain on fair value adjustment	12,955,000	0	0
Foreign currency exchange gain (loss)	71,000	117,000	(413,000)
Interest income	1,123,000	551,000	88,000
Other expense, net	108,000	(227,000)	(20,000)
Total other (expense) income, net	(6,740,000)	235,000	(6,097,000)
Net loss before income taxes	(60,768,000)	(62,570,000)	(77,657,000)
(Provision) benefit for income taxes	(850,000)	77,000	(45,000)
Net loss	$ (61,618,000)	$ (62,493,000)	$ (77,702,000)
Basic net loss per share (in dollars per share)	$ (4.94)	$ (7.61)	$ (12.59)
Diluted net loss per share ( in dollars per share)	$ (4.94)	$ (7.61)	$ (12.59)
Weighted average shares outstanding, basic (in shares)	12,477	8,216	6,173
Weighted average shares outstanding, diluted (in shares)	12,477	8,216	6,173
Other comprehensive loss:
Net loss	$ (61,618,000)	$ (62,493,000)	$ (77,702,000)
Net unrealized gain (loss) on available-for-sale investments	29,000	(14,000)	(34,000)
Foreign currency translation adjustment	(241,000)	(326,000)	(117,000)
Comprehensive loss	(61,830,000)	(62,833,000)	(77,853,000)
Nonrelated Party
Other (expense) income:
Interest expense	(5,926,000)	(2,274,000)	(15,545,000)
(Loss) gain on extinguishment of debt	(6,499,000)	3,565,000	9,793,000
Related Party
Other (expense) income:
Interest expense	(1,817,000)	(1,497,000)	0
(Loss) gain on extinguishment of debt	$ (6,755,000)	$ 0	$ 0