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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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