Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Net loss	$ (179,217)	$ (113,163)
Reconciliation of net loss to net cash used in operating activities:
Depreciation and amortization	6,039	2,715
Equity-based compensation	25,745	22,092
Other non-cash items, net	6,099	2,064
Changes in:
Accounts receivable	162	(6)
Prepaid expenses and other assets	4,611	(5,068)
Accounts payable and accrued expenses	(1,616)	(5,770)
Deferred revenue	(762)	(539)
Operating lease assets and liabilities	3,854	778
Other liabilities, net	(154)	(3,766)
Net cash used in operating activities	(135,239)	(100,663)
Investing activities:
Purchase of property, plant and equipment	(15,350)	(7,024)
Purchases of marketable securities	(323,140)	(323,975)
Maturities of marketable securities	223,975	163,101
Net cash used in investing activities	(114,515)	(167,898)
Financing activities:
Proceeds from issuance of common shares, net of issuance costs	0	214,592
Proceeds from exercise of options and ESPP contributions, net of issuance costs	10,649	11,399
Net cash provided by financing activities	10,649	225,991
Effect of exchange rate changes on cash	(27)	5
Decrease in cash	(239,132)	(42,565)
Cash, cash equivalents and restricted cash, beginning of period	939,944	1,185,468
Cash, cash equivalents and restricted cash, end of period	700,812	1,142,903
Supplemental disclosure of non-cash investing and financing activities
Property and equipment purchases in accounts payable and accrued expenses	5,888	8,847
Equity issuance costs in accounts payable and accrued expenses	217	$ 2,868
Leasehold improvements paid directly by landlord	$ 13,015