Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Operating activities
Net loss	$ (177,667)	$ (164,824)
Adjustments to reconcile net loss from operations to net cash used in operating activities:
Depreciation and amortization	2,941	3,597
Stock-based compensation expense	20,799	21,876
Net accretion of discount on marketable securities	(5,136)	(5,738)
Gain on disposal of property and equipment	(39)	(150)
Non-cash operating lease expense	5,659	5,263
Realized gain on investments	(153)	0
Changes in operating assets and liabilities:
Accounts receivable, net	(952)	(45)
Inventory	(4,861)	(7,179)
Prepaid expenses and other current and non-current assets	486	2,103
Accounts payable	268	(6,837)
Accrued expenses and other current liabilities	(6,425)	(1,161)
Operating lease liabilities	(7,376)	(6,713)
Other non-current liabilities	0	(2,123)
Net cash used in operating activities	(172,456)	(161,931)
Investing activities
Purchases of marketable securities	(348,604)	(232,486)
Proceeds from maturities and sales of marketable securities	510,669	337,453
Purchases of property and equipment	(299)	(396)
Proceeds from sale of equipment	40	150
Net cash provided by investing activities	161,806	104,721
Financing activities
Net proceeds from stock option exercises and employee stock purchase plan	6,963	2,704
Net cash provided by financing activities	6,963	2,704
Net change in cash and cash equivalents	(3,687)	(54,506)
Cash and cash equivalents at beginning of the period	88,205	139,259
Cash and cash equivalents at end of the period	84,518	84,753
Supplemental disclosure of non-cash investing and financing transactions
Additions to property and equipment in accounts payable and accrued expenses	42	6
Net cash taxes (returned) paid	$ (603)	$ 801