Summary of Significant Accounting Policies - Preferred Stock Discount (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Feb. 28, 2021	Sep. 30, 2021
Antidilutive Common Stock Equivalents Excluded from Computation of Diluted Net Loss Per Share
Conversion of Series X Preferred Stock into common stock		$ 168,920
Private Placement
Antidilutive Common Stock Equivalents Excluded from Computation of Diluted Net Loss Per Share
Conversion of Series X Preferred Stock into common stock		900
Private Placement | Series X redeemable convertible preferred stock
Antidilutive Common Stock Equivalents Excluded from Computation of Diluted Net Loss Per Share
Beneficial conversion feature	$ 19,600
Issuance costs	$ 5,700
Non cash return		$ 24,400