Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (151,059)	$ (181,702)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	25,061	38,621
Depreciation and amortization expense	14,605	15,193
Impairment of other investments	13,001	12,923
Net amortization and accretion on marketable securities	(11,716)	(6,212)
Non-cash lease income	(1,591)	(1,344)
Change in fair value of success payment liabilities	(669)	(3,309)
Loss on property and equipment disposals, net	417	1,072
Gain on marketable equity security	(47)	0
Changes in operating assets and liabilities:
Prepaid expenses, other current assets and other assets	(1,861)	(23)
Accounts payable	(1,198)	1,039
Accrued liabilities and other current liabilities	4	1,020
Other non-current liabilities	(99)	(337)
Net cash used in operating activities	(115,152)	(123,059)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchases of property and equipment	(420)	(2,661)
Purchases of marketable securities	(355,905)	(220,095)
Maturities of marketable securities	425,244	507,494
Net cash provided by investing activities	68,919	284,738
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from exercise of stock options	155	155
Proceeds from employee stock purchase plan	810	1,163
Taxes paid related to net share settlement of equity awards	(76)	(334)
Net cash provided by financing activities	889	984
Net (decrease) increase in cash, cash equivalents and restricted cash	(45,344)	162,663
Cash, cash equivalents and restricted cash at beginning of period	145,931	123,834
Cash, cash equivalents and restricted cash at end of period	100,587	286,497
Represented by:
Cash and cash equivalents	100,299	286,214
Restricted cash	288	283
Total	100,587	286,497
SUPPLEMENTAL CASH FLOW INFORMATION
Cash paid for amounts included in the measurement of lease liabilities	8,449	8,030
Non-cash investing and financing activities:
Purchases of property and equipment included in accounts payable and accrued liabilities	$ 23	$ 2