Organization and Operations - Stock Purchase Agreement and Series X Preferred Stock (Details) - USD ($) $ in Thousands				6 Months Ended
	Jun. 30, 2021	Jun. 02, 2021	Jan. 28, 2021	Jun. 30, 2021	Feb. 28, 2021	Dec. 31, 2020
Stock Purchase Agreement and Series X Preferred Stock
Net proceeds from issuance of private placement				$ 104,261
Series X Preferred Stock at Transaction Date					88,882
Common Stock Issuable Upon Conversion at Transaction Date					88,882,000
Percentage of beneficial ownership initially, after conversion	9.99%			9.99%
Minimum
Stock Purchase Agreement and Series X Preferred Stock
Percentage of beneficial ownership thereafter, after conversion	4.99%			4.99%
Maximum
Stock Purchase Agreement and Series X Preferred Stock
Percentage of beneficial ownership thereafter, after conversion	19.99%			19.99%
Quellis Biosciences, Inc | Stock Purchase Agreement
Stock Purchase Agreement and Series X Preferred Stock
Beneficial conversion feature				$ 19,600
Series X redeemable convertible preferred stock
Stock Purchase Agreement and Series X Preferred Stock
Issuance of preferred stock in a private offering of public equity, net of issuance costs (in shares)				35,573
Number of shares of common stock into which each share of Series X Preferred Stock may be converted		1,000		1,000
Conversion of preferred stock into common stock (in shares)	53,532
Issuance of common stock upon the conversion of preferred stock (in shares)	53,531,797
Preferred stock, outstanding (in shares)	32,545			32,545		0
Series X redeemable convertible preferred stock | Quellis Biosciences, Inc
Stock Purchase Agreement and Series X Preferred Stock
Number of shares of common stock into which each share of Series X Preferred Stock may be converted			1,000
Series X redeemable convertible preferred stock | Quellis Biosciences, Inc | Stock Purchase Agreement
Stock Purchase Agreement and Series X Preferred Stock
Issuance of preferred stock in a private offering of public equity, net of issuance costs (in shares)				35,573
Gross proceeds from issuance of preferred stock in a private offering				$ 110,000
Net proceeds from issuance of private placement				104,300
Issuance costs				$ 5,700
Outstanding shares issued in merger
Stock Purchase Agreement and Series X Preferred Stock
Series X Preferred Stock at Transaction Date					50,504
Common Stock Issuable Upon Conversion at Transaction Date					50,504,000
Outstanding shares issued in February 2021 Financing
Stock Purchase Agreement and Series X Preferred Stock
Series X Preferred Stock at Transaction Date					35,573
Common Stock Issuable Upon Conversion at Transaction Date					35,573,000
Warrants assumed in merger
Stock Purchase Agreement and Series X Preferred Stock
Series X Preferred Stock at Transaction Date					2,805
Common Stock Issuable Upon Conversion at Transaction Date					2,805,000