Nature of Business and Plan of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Net loss			$ (102,131)	$ (75,760)
Accumulated deficit	$ (1,433,971)		(1,433,971)		$ (1,331,840)
Total revenues	9,210	$ 18,189	41,864	46,501
Cash and cash equivalents	$ 245,761	$ 188,217	$ 245,761	$ 188,217	$ 293,856	$ 176,225
Number of months Capital resources meets capital expenditures			12 months
Product
Total revenues			$ 0