CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net loss	$ (104,367)	$ (104,631)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,145	2,305
Inventory reserve	170	1,363
Change in fair value of warrant liability	(68)	(922)
Stock-based compensation	18,153	18,358
Amortization of right-of-use assets	2,278	2,147
Realized loss on available-for-sale securities	0	29
Amortization of premium and accretion of discount on available-for-sale securities, net	(2,102)	641
Changes in operating assets and liabilities:
Accounts receivable	2,118	(1,046)
Inventories	89	(580)
Other current assets	(147)	(615)
Other noncurrent assets	(204)	(4)
Accounts payable	(2,402)	1,751
Accrued liabilities	(6,291)	(456)
Accrued employee costs	139	1,283
Lease liability	(2,253)	(2,133)
Other current liabilities	250	(583)
Net cash used in operating activities	(91,492)	(83,093)
Cash flows from investing activities:
Purchase of property, plant and equipment	(3,423)	(5,967)
Purchase of available-for-sale securities	(97,642)	(143,730)
Proceeds from maturities of available-for-sale securities	165,597	284,176
Net cash provided by investing activities	64,532	134,479
Cash flows from financing activities:
Payments of taxes withheld on net settled vesting of restricted stock units	(62)	(613)
Proceeds from exercise of warrants	0	1
Proceeds from exercise of stock options	152	301
Net cash (used in) provided by financing activities	90	(311)
Net (decrease) increase in cash and cash equivalents	(26,870)	51,075
Beginning cash and cash equivalents	67,420	66,810
Ending cash and cash equivalents	40,550	117,885
Supplemental disclosures of cash flow information:
Cash paid for interest	0	0
Cash paid for income taxes	0	0
Supplemental disclosures of non-cash investing and financing activities:
Purchases of property and equipment recorded in accounts payable and accrued liabilities	604	(97)
Taxes withheld on net settled vesting of restricted stock units	0	107
Right-of-use asset obtained in exchange for lease liability	$ 2,646	$ 0