Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities
Net loss	$ (38,608)	$ (29,711)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Stock-based compensation	9,426	8,080
Depreciation of property and equipment	1,017	117
Non-cash lease expense	215	594
Non-cash interest expense, net	1,228	997
Changes in assets and liabilities:
Accounts receivable, net	(2,370)	7
Accounts receivable from related party	14	(9,980)
Inventory	(2,046)	0
Prepaids and other current assets	(2,162)	583
Other assets	32	(4)
Accounts payable	(1,329)	1,201
Operating lease liabilities	(664)	6,342
Other liabilities	(960)	418
Deferred revenue from related party	45,038	(211)
Net cash provided by (used in) operating activities	8,831	(21,567)
Investing activities
Purchases of property and equipment, net	(224)	(10,880)
Purchases of investments	(91,498)	(95,278)
Maturities of investments	70,385	166,826
Net cash (used in) provided by investing activities	(21,337)	60,668
Financing activities
Proceeds from exercise of stock options and employee stock purchase plan	6,231	2,163
Employees' tax withheld and paid for with restricted stock units	(3,126)	(5,013)
Net cash provided by (used in) financing activities	3,105	(2,850)
Net (decrease) increase in cash, cash equivalents and restricted cash	(9,401)	36,251
Cash, cash equivalents and restricted cash at beginning of period	51,058	33,377
Cash, cash equivalents and restricted cash at end of period	41,657	69,628
Supplemental disclosures of cash flow information
Cash paid for interest	488	509
Right-of-use assets obtained in exchange for lease obligations	1	300
Purchases of property and equipment, net recorded in accounts payable and accrued liabilities	$ 6	$ 2,807