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Equity Transactions - Rights Offering - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Mar. 05, 2020 | Feb. 11, 2020 | Dec. 31, 2021 | Dec. 31, 2020
Class Of Stock [Line Items] |  |  |  |
Common stock, par value |  |  | $ 0.001 | $ 0.001
Aggregate issuance costs |  |  | $ 248 | $ 953
Common Stock [Member] |  |  |  |
Class Of Stock [Line Items] |  |  |  |
Issuance of Common Stock, conversion of Preferred Stock to Common Stock |  |  |  | $ 2
Issuance of stock, shares | 1,046,249 |  | 475,469 | 8,025,119
Aggregate issuance costs |  |  |  | $ 700
Series C Preferred Stock [Member] |  |  |  |
Class Of Stock [Line Items] |  |  |  |
Issuance of Common Stock, conversion of Preferred Stock to Common Stock | $ 20,600 | $ 30,000 |  |
Right to purchase common stock shares |  | 0.152 |  |
Common stock, par value |  | $ 9.00 |  |
Issuance of stock, shares | 2,287 |  |  |
Aggregate issuance costs | $ 100 |  |  |
Share price | $ 9.22 |  |  |
Intrinsic value of beneficial conversion feature |  |  |  | $ 500
Common Stock and Series C Preferred Stock [Member] |  |  |  |
Class Of Stock [Line Items] |  |  |  |
Issuance of Common Stock, conversion of Preferred Stock to Common Stock | $ 30,000 |  |  |
Amount of agreed to purchase offered shares and not subscribed shares value under rights offering |  |  | $ 30,000 |
Aggregate issuance costs | $ 500 |  |  |
Series A Convertible Preferred Stock [Member] |  |  |  |
Class Of Stock [Line Items] |  |  |  |
Issuance of stock, shares |  |  | 2,220 |
Share price | $ 8.98 |  |  |

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