Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Operating activities
Net loss	$ (145,941)	$ (101,657)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	7,834	4,845
Noncash lease expense	5,259	2,217
Share-based compensation expense	31,376	17,518
Intangible assets amortization	1,270	1,275
Investment amortization	5,956	(484)
Benefit from income tax		(1,116)
Other	(9)	62
Changes in operating assets and liabilities:
Accounts receivable, net	(7,075)	802
Inventory	(4,168)	(1,667)
Prepaid expenses and other current assets	(2,239)	(3,886)
Accounts payable and accrued liabilities	5,518	30
Operating lease liabilities	9,935	(282)
Deferred revenue	(46,345)	(27,281)
Other	(272)	(215)
Net cash used in operating activities	(138,901)	(109,839)
Investing activities
Purchases of property and equipment	(52,501)	(9,433)
Purchases of marketable securities	(238,001)	(299,786)
Proceeds from sales and maturities of marketable securities	404,500	532,224
Net cash provided by investing activities	113,998	223,005
Financing activities
Proceeds from exercise of stock options	23,439	15,495
Proceeds from public offering of common stock, net of underwriting discounts and commissions		272,160
Payment of public offering costs, net		(321)
Proceeds from initial capital contributions for Spin Technologies, Inc.	429
Net cash provided by financing activities	23,868	287,334
Net (decrease) increase in cash, cash equivalents and restricted cash	(1,035)	400,500
Cash, cash equivalents and restricted cash at beginning of year	125,574	98,714
Cash, cash equivalents and restricted cash at end of period	124,539	499,214
Noncash investing and financing activities
Purchases of equipment included in accounts payable and accrued liabilities	$ 8,133	3,582
Derecognition of lease financing arrangements upon adoption of guidance on accounting for leases		$ 36,607