Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities
Net loss	$ (215,975)	$ (167,870)	$ (281,584)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	68,201	63,615	84,422
Amortization of premiums and accretion of discounts on investment securities	(2,736)	2,404	1,470
Amortization of intangible assets	0	1,108	1,477
(Gain) loss on strategic investment	(3,542)	(2,329)	997
Depreciation	2,026	2,236	1,455
Loss on disposal of assets	0	0	281
Non-cash in-process research and development	0	0	44,280
Changes in operating assets and liabilities:
Accounts receivable, net	2,171	(16,119)	(12,466)
Interest and other receivables	93	1,057	58
Inventory	2,415	(4,210)	(3,320)
Prepaid expenses and other current assets	2,494	1,802	(7,088)
Operating lease right-of-use assets	6,566	6,287	4,280
Other assets	(48)	10	182
Accounts payable	5,870	(1,617)	1,271
Accrued liabilities	24,306	(8,455)	27,569
Operating lease liabilities	(7,916)	(5,433)	(1,769)
Long-term liabilities	2,040	1,854	2,319
Net cash used in operating activities	(114,035)	(125,660)	(136,166)
Cash flows from investing activities
Purchases of investment securities	(363,174)	(492,797)	(339,908)
Maturities of investment securities	436,415	422,817	540,004
Net purchases of property and equipment	0	(1,122)	(7,587)
Net cash (used in) provided by investing activities	73,241	(71,102)	192,509
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	8,199	18,162	80,996
Net cash provided by financing activities	8,199	18,162	80,996
Effect of exchange rate changes on cash	6	7	(8)
Net (decrease) increase in cash, cash equivalents and restricted cash	(32,589)	(178,593)	137,331
Cash, cash equivalents and restricted cash
Beginning of period	153,205	331,798	194,467
End of period	120,616	153,205	331,798
Supplemental disclosure of cash flow information:
Cash paid for income taxes	2,190	1,038	1,113
Supplemental disclosure of noncash information:
Property and equipment purchases in accounts payable and accrued liabilities	0	0	130
Value of common stock issued in connection with asset acquisition	$ 0	$ 0	$ 44,280