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v3.23.1

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions |  |  | 12 Months Ended |
--- | --- | --- | --- | ---
Jan. 11, 2022 | Sep. 21, 2021 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Mar. 31, 2021
Class Of Stock [Line Items] |  |  |  |  |  |
Preferred stock, par value |  |  | $ 0.001 | $ 0.001 |  |
Warrant exercise price per share |  |  | $ 0.001 |  |  |
Common Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Warrants available for exercise |  |  | 1,145,631 |  |  |
Series X1 Preferred Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Shares of common stock issued upon conversion of each share of preferred stock |  |  | 2,789,301 |  |  |
Warrants available for exercise |  |  | 50,207.419 |  |  |
Series X1 Non-voting Convertible Preferred Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Preferred stock, par value |  |  | $ 0.001 | $ 0.001 |  |
Jeffries LLC [Member] | ATM Program [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Common stock number of shares issued |  |  | 0 | 0 |  |
Equity distribution agreement maximum value of common shares issuable |  |  |  |  |  | $ 75.0
Public float minimum balance to be maintained |  |  | $ 75.0 |  |  |
Jeffries LLC [Member] | Maximum [Member] | ATM Program [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Equity distribution agreement maximum value of common shares issuable |  |  | $ 10.5 |  |  |
Series X Exchange Agreement [Member] | BVF Exchanging Stockholders, Series X Exchanging Stockholders [Member] | Common Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Conversion of stock, shares converted |  |  |  |  | 344,666 |
Series X Exchange Agreement [Member] | BVF Exchanging Stockholders, Series X Exchanging Stockholders [Member] | Series X Non-voting Convertible Preferred Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Conversion of stock, shares issued |  |  |  |  | 6,203.98 |
Series X1 Exchange Agreement [Member] | BVF Exchanging Stockholders, Series X Exchanging Stockholders [Member] | Common Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Conversion of stock, shares converted | 550,000 |  |  |  |  |
Series X1 Exchange Agreement [Member] | BVF Exchanging Stockholders, Series X Exchanging Stockholders [Member] | Series X1 Non-voting Convertible Preferred Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Conversion of stock, shares issued | 9,899.99 |  |  |  |  |
Warrant Exchange Agreement and Exchange Agreements [Member] | BVF Exchanging Stockholders | Common Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Warrants to purchase common stock |  |  |  |  | 509,117 |
September 2021 Warrant Exchange Agreement [Member] | Common Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Warrants issued |  | 298,692 |  |  |  |
September 2021 Warrant Exchange Agreement [Member] | Series X1 Non-voting Convertible Preferred Stock [Member] | Common Stock [Member] |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |
Warrants exercisable for exchange |  | 5,376.456 |  |  |  |

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