CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net loss	$ (45,191)	$ (91,047)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,307	1,029
Share-based compensation expense	12,707	12,843
Non-cash lease expense	1,481	1,193
Amortization of premiums and accretion of discounts on short-term investments	240	603
Loss on disposal of property and equipment	34
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(7,421)	(196)
Accounts receivable, net	(3,823)	(2,551)
Inventory	(16,241)	(6,381)
Other long-term assets	2,918	(279)
Accounts payable	654	3,654
Accrued expenses and other liabilities	(1,889)	2,753
Operating lease liabilities	(1,436)	(863)
Deferred revenue	12,000
Other long-term liabilities	(10)	337
Net cash used in operating activities	(44,670)	(78,905)
Cash flows from investing activities:
Proceeds from sale of property and equipment	91
Purchases of property and equipment	(115)	(113)
Purchases of short-term investments	(55,734)	(97,460)
Proceeds from the maturities of short-term investments	71,300	248,400
Intangible asset acquired		(20,000)
Net cash provided by investing activities	15,542	130,827
Cash flows from financing activities:
Proceeds from issuance of Class A common shares under incentive award plans and employee share purchase plans	1,558	1,993
Payments in connection with Common Stock tendered for employee tax obligations	(593)
Net cash provided by financing activities	965	1,993
Net increase (decrease) in cash, cash equivalents and restricted cash	(28,163)	53,915
Cash, cash equivalents and restricted cash at beginning of period	122,470	114,248
Cash, cash equivalents and restricted cash at end of period	94,307	$ 168,163
Supplemental information:
Cash paid for income taxes	$ 3,293