Summary of Significant Accounting Policies - Redeemable Convertible Preferred Stock (Details) - USD ($) $ in Thousands	8 Months Ended	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2019
Class of Stock [Line Items]
Conversion of preferred stock to common stock upon IPO	$ 144,140	$ 144,140
Common Stock
Class of Stock [Line Items]
Conversion of preferred stock to common stock upon IPO (in shares)	23,178,555