Income Taxes - Deferred Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Taxes
Valuation allowance	$ 396,079	$ 222,521
Effect Of Tax Cuts And Jobs Act Of 2017 [Abstract]
Corporate tax rate	21.00%	21.00%	21.00%
Deferred tax assets
Net operating loss carryforwards	$ 315,552	$ 177,899
Intangibles	4,443
Research and development tax credit carryforwards	38,725	24,332
Reserves and accruals	14,098	21,770
Lease Liabilities	16,843	7,123
Deferred revenue	6,363	6,386
Stock based compensation	15,928	10,673
Total deferred tax assets before valuation allowance	411,952	248,183
Less: valuation allowance	(396,079)	(222,521)
Deferred tax assets, net	15,873	25,662
Deferred tax liabilities
Convertible debt		(19,143)
Right-of-use lease assets	(15,873)	(6,519)
Net deferred tax assets