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Equity Transactions - Underwritten Public Offering - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Oct. 01, 2020 | Sep. 15, 2020 | Mar. 05, 2020 | Dec. 31, 2021 | Dec. 31, 2020
Class Of Stock [Line Items] |  |  |  |  |
Net proceeds from issuance of common stock |  |  |  | $ 7,831 | $ 13,166
Series D Convertible Preferred Stock [Member] |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |
Issuance of stock, shares |  |  |  | 3,215,000 |
Common Stock [Member] |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |
Issuance of stock, shares |  |  | 1,046,249 | 475,469 | 8,025,119
Underwritten Public Offering Member |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |
Underwritten offering, exercisable term |  | 30 days |  |  |
Gross proceeds from issuance of common and preferred stock |  | $ 80,000 |  |  |
Net proceeds from issuance of common and preferred stock |  | $ 74,700 |  |  |
Underwritten Public Offering Member | Series D Convertible Preferred Stock [Member] |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |
Issuance of stock, shares |  | 3,215,000 |  |  |
Share price |  | $ 10.00 |  |  |
Underwritten Public Offering Member | Common Stock [Member] |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |
Issuance of stock, shares | 1,200,000 | 4,785,000 |  |  |
Share price | $ 10.00 | $ 10.00 |  |  |
Net proceeds from issuance of common stock | $ 11,200 |  |  |  |
Underwritten Public Offering Member | Maximum [Member] |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |
Additional number of common stock issuable |  | 1,200,000 |  |  |

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