Summary of Significant Accounting Policies - Liquidity Matters (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Jul. 31, 2021	Apr. 30, 2020	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Policies
Net (loss) income			$ (145,151)	$ (116,026)	$ (283,746)	$ (179,879)
Accumulated deficit			1,678,582		1,678,582		$ 1,394,836
Cash, cash equivalents and restricted cash			91,384	$ 63,039	91,384	$ 63,039	84,614	$ 48,855
Marketable securities			547,353		547,353		829,896
Short-term Credit Line, outstanding balance			$ 50,086		$ 50,086		$ 50,052
Common stock, shares issued			96,903,000		96,903,000		95,140,000
Convertible Notes
Policies
Outstanding principal balance		$ 287,500	$ 287,500		$ 287,500
Per annum interest rate (as a percent)		2.25%			2.25%
Net proceeds		$ 278,300
Equity offering
Policies
Common stock, shares issued	5,175,000
Stock issued (in dollars per share)	$ 113
Payment of offering expenses	$ 400
Proceeds from issuance of common stock	$ 551,200