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Common Stock Warrants - Summary of Outstanding Warrants to Purchase Shares of Common Stock (Detail) - USD ($) $ / shares in Units, $ in Thousands | Mar. 31, 2022 | Mar. 03, 2022 | Dec. 31, 2021 | Nov. 09, 2021 | Mar. 23, 2021 | Nov. 02, 2020 | Nov. 29, 2019
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Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 14,023,726 |  | 13,257,160 |  |  |  |
Class Of Warrant Or Right. Aggregate Proceeds From Warrants Issued |  | $ 3,000 |  | $ 10,000 | $ 435 |  | $ 21,000
Class of Warrant or Right, Additional Exercise Price of Warrants or Rights |  |  |  |  | $ 0.01 | $ 0.01 | $ 0.001
Funded |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) |  | $ 1.79 |  | $ 4.97 | $ 8.69 |  |
Pre Funded Warrant |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) |  |  |  |  |  |  | 11.999
Class B Warrants |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) |  |  |  |  |  |  | $ 15.00
Issuance On October 25, 2016 |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 19.78 |  |  |  |  |  |
Issuance On October 25, 2016 | Legacy Warrants |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 5,155 |  |  |  |  |  |
Issuance On December 28, 2017 One |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 19.78 |  |  |  |  |  |
Issuance On December 28, 2017 One | Legacy Warrants |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 115,916 |  |  |  |  |  |
Issuance On September 12, 2018 One |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 19.78 |  |  |  |  |  |
Issuance On September 12, 2018 One | Legacy Warrants |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 20,220 |  |  |  |  |  |
Issuance On October 19, 2018 |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 19.78 |  |  |  |  |  |
Issuance On October 19, 2018 | Legacy Warrants |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 20,016 |  |  |  |  |  |
Issuance On March 13, 2019 |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 19.78 |  |  |  |  |  |
Issuance On March 13, 2019 | Legacy Warrants |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 5,000 |  |  |  |  |  |
Issuance On April 16, 2019 |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 13.20 |  |  |  |  |  |
Issuance On April 16, 2019 | Class A Warrant |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 3,866,154 |  |  |  |  |  |
Issuance On November 29, 2019 |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 1.80 |  |  |  |  |  |
Issuance On November 29, 2019 | Class B Warrants |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 5,416,567 |  |  |  |  |  |
Issuance On November 29, 2019 One |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 12.00 |  |  |  |  |  |
Issuance On November 29, 2019 One | Pre Funded Warrant |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 1,750,000 |  |  |  |  |  |
Issuance On March 23, 2021 |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Exercise Price (usd per share) | $ 8.70 |  |  |  |  |  |
Issuance On March 23, 2021 | Pre Funded Warrant |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 50,000 |  |  |  |  |  |
Issuance on November Nine Two Thousand Twenty One |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 2,008,032 |  |  |  |  |  |
Exercise Price (usd per share) | $ 4.98 |  |  |  |  |  |
Issuance on March 3 2022 |  |  |  |  |  |  |
Class of Warrant or Right [Line Items] |  |  |  |  |  |  |
Number of Shares of Common Stock Issuable (in shares) | 766,666 |  |  |  |  |  |
Exercise Price (usd per share) | $ 1.80 |  |  |  |  |  |

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