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Stockholders' Equity - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended
	Jan. 11, 2022	Mar. 31, 2022	Mar. 31, 2021
Series X1 Preferred Stock [Member]
Class Of Stock [Line Items]
Warrants available for exercise		50,207.419
Shares of common stock issued upon conversion of each share of preferred stock		2,789,301
Common Stock [Member]
Class Of Stock [Line Items]
Warrants available for exercise		1,145,631
BVF Exchanging Stockholders [Member] | Series X1 Exchange Agreement [Member] | Series X1 Preferred Stock [Member]
Class Of Stock [Line Items]
Conversion of stock, shares issued	9,899.99
BVF Exchanging Stockholders [Member] | Common Stock [Member] | Series X1 Exchange Agreement [Member]
Class Of Stock [Line Items]
Conversion of stock, shares converted	550,000
ATM Program [Member] | Jeffries LLC [Member]
Class Of Stock [Line Items]
Equity distribution agreement maximum value of common shares issuable			$ 75.0
Public float minimum balance to be maintained		$ 75.0
Common stock number of shares issued		0
ATM Program [Member] | Maximum [Member] | Jeffries LLC [Member]
Class Of Stock [Line Items]
Equity distribution agreement maximum value of common shares issuable		$ 16.4

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