Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
OPERATING ACTIVITIES
Net Income (Loss)	$ (86,277)	$ (92,966)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	34,424	33,673
Depreciation and amortization	5,578	3,942
Loss on disposal of property and equipment	399	332
Net accretion of discount on available-for-sale securities	(11,548)	(833)
Provision for inventory excess and obsolescence	872	507
Non-cash operating lease expense	211	1,655
Changes in operating assets and liabilities:
Accounts receivable, net	302	(2,874)
Prepaid expenses and other assets	(1,313)	(1,081)
Inventory	(1,948)	(1,590)
Accounts payable	(987)	(1,553)
Deferred revenue	73	(243)
Accrued liabilities and other liabilities	1,149	251
Net cash used in operating activities	(59,065)	(60,780)
INVESTING ACTIVITIES
Purchases of property and equipment	(7,309)	(10,265)
Proceeds from disposal of property and equipment	0	170
Purchase of available-for-sale securities	(403,092)	(366,268)
Proceeds from sale of available-for-sale securities	2,990	0
Proceeds from maturities of available-for-sale securities	445,315	253,645
Net cash provided by (used in) investing activities	37,904	(122,718)
FINANCING ACTIVITIES
Repurchase of Class A common stock	(13)	(20)
Proceeds from exercise of Class A common stock options	97	3,138
Proceeds from issuance of common stock in connection with employee stock purchase plan	368	775
Net cash provided by financing activities	452	3,893
Net decrease in cash, cash equivalents and restricted cash	(20,709)	(179,605)
Cash, cash equivalents and restricted cash, beginning of period	53,732	233,337
Cash, cash equivalents and restricted cash, end of period	33,023	53,732
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITIES
Property and equipment purchases included in accounts payable and accrued expenses	415	354
Inventory transferred to property and equipment	1,332	928
Property and equipment transferred to inventory	121	327
Prepaid expenses and other assets transferred to fixed asset	$ 181	$ 0