Stock-based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Stock-based compensation expense
Stock-based compensation expense	$ 7,944	$ 8,179	$ 15,421	$ 14,275
Research and development
Stock-based compensation expense
Stock-based compensation expense	3,301	2,860	6,488	5,497
General and administrative
Stock-based compensation expense
Stock-based compensation expense	4,643	5,319	8,933	8,778
Stock options
Stock-based compensation expense
Stock-based compensation expense	$ 7,944	$ 8,179	$ 15,421	$ 14,275