Net Loss and Net Loss Per Share - Calculation of Basic and Diluted Net Loss (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Numerator:
Net loss	$ (145,224)	$ (325,991)	$ (290,581)
Denominator:
Weighted average number of shares outstanding, basic (in shares)	137,370,897	125,530,703	121,524,795
Net loss per share, basic (usd per share)	$ (1.06)	$ (2.60)	$ (2.39)
Net loss per share, diluted (usd per share)	$ (1.06)	$ (2.60)	$ (2.39)