Organization and Operations - Stock Purchase Agreement and Series X Preferred Stock (Details)		1 Months Ended	9 Months Ended
	Sep. 30, 2021 shares	Feb. 28, 2021 USD ($)	Sep. 30, 2021 USD ($) shares	Jun. 02, 2021	Jan. 28, 2021	Dec. 31, 2020 shares
Stock Purchase Agreement and Series X Preferred Stock
Net proceeds from issuance of private placement			$ 104,261,000
Issuance of common stock upon the conversion of preferred stock (in shares) | shares	9,103,664
Minimum
Stock Purchase Agreement and Series X Preferred Stock
Common stock, percentage of beneficial ownership initially, after conversion	4.99%		4.99%
Common stock, percentage of beneficial ownership thereafter, after conversion	4.99%		4.99%
Maximum
Stock Purchase Agreement and Series X Preferred Stock
Common stock, percentage of beneficial ownership initially, after conversion	9.99%		9.99%
Common 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			$ 19,600,000
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) | shares			35,573
Shares issued		$ 88,882
Number of shares of common stock into which each share of Series X Preferred Stock may be converted	166.67		166.67	166.67
Conversion of preferred stock into common stock (in shares) | shares	54,622
Number of common shares issuable upon conversion of preferred stock (in shares) | shares	5,242,501		5,242,501
Preferred stock, outstanding (in shares) | shares	31,455		31,455			0
Series X redeemable convertible preferred stock | Outstanding shares issued in merger
Stock Purchase Agreement and Series X Preferred Stock
Shares issued		50,504
Series X redeemable convertible preferred stock | Outstanding shares issued in February 2021 Financing
Stock Purchase Agreement and Series X Preferred Stock
Shares issued		35,573
Series X redeemable convertible preferred stock | Warrants assumed in merger
Stock Purchase Agreement and Series X Preferred Stock
Shares issued		$ 2,805
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	166.67		166.67		166.67
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) | shares			35,573
Gross proceeds from issuance of preferred stock in a private offering			$ 110,000,000.0
Net proceeds from issuance of private placement			104,300,000
Issuance costs			$ 5,700,000