Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
OPERATING ACTIVITIES
Net loss	$ (68,478)	$ (70,441)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	26,810	25,513
Depreciation and amortization	3,998	2,839
Loss on disposal of property and equipment	258	261
Net amortization (accretion) of premium (discount) on available-for-sale securities	(8,545)	307
Provision for inventory excess and obsolescence	825	0
Non-cash operating lease expense	164	1,497
Changes in operating assets and liabilities:
Accounts receivable and other receivables	(728)	(2,234)
Prepaid expenses and other assets	(1,080)	(1,036)
Inventory	(1,634)	(2,372)
Accounts payable	(1,353)	(443)
Deferred revenue	52	(51)
Accrued liabilities and other liabilities	836	(364)
Net cash used in operating activities	(48,875)	(46,524)
INVESTING ACTIVITIES
Payments for (Proceeds from) Property, Plant, and Equipment	(5,470)	(5,292)
Proceeds from disposal of property and equipment	0	170
Purchase of available-for-sale securities	(318,049)	(202,748)
Proceeds from sale of available-for-sale securities	2,990	0
Proceeds from maturities of available-for-sale securities	352,322	87,863
Net cash provided by (used in) investing activities	31,793	(120,007)
FINANCING ACTIVITIES
Repurchase of Class A common stock	(13)	(20)
Proceeds from exercise of Class A common stock options	91	1,387
Net cash provided by financing activities	270	1,787
Net decrease in cash, cash equivalents and restricted cash	(16,812)	(164,744)
Cash, cash equivalents and restricted cash, beginning of period	53,732	233,337
Cash, cash equivalents and restricted cash, end of period	36,920	68,593
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITIES
Property and equipment purchases included in accounts payable and accrued expenses	250	828
Inventory transferred to property and equipment	1,211	0
Lease liability obtained in exchange for right-of-use assets	514	6,855
Class A common stock
FINANCING ACTIVITIES
Proceeds from issuance of Class A common stock in connection with employee stock purchase plan	$ 192	$ 420