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Subsequent Events - Additional Information (Details) - USD ($) |  |  |  |  | 1 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Feb. 17, 2021 | Jan. 08, 2021 | Oct. 23, 2020 | Oct. 02, 2020 | Feb. 28, 2021 | Sep. 30, 2020 | Dec. 31, 2020 | Dec. 31, 2019
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Proceeds from sale of common stock |  |  |  |  |  |  | $ 4,007,000 | $ 15,964,000
Common Stock [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  |  | 184,666
Common Stock [Member] | 2020 Repurchase Agreement [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  | 180,701 |  | 0 | 353,113 |
Proceeds from sale of common stock |  |  |  |  |  |  | $ 700,000 |
Common Stock [Member] | Canaccord Genuity LLC [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Common stock issued (in shares) |  |  |  |  |  |  | 1,616,331 |
Proceeds from sale of common stock |  |  | $ 10,000,000 |  |  |  | $ 3,200,000 |
Subsequent Event [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Number of securities called by warrant or right |  |  |  |  | 896,500 |  |  |
Proceeds from warrant exercises |  |  |  |  | $ 2,000,000 |  |  |
Subsequent Event [Member] | Common Stock [Member] | 2020 Repurchase Agreement [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Common stock issued (in shares) | 985,186 |  |  |  |  |  |  |
Proceeds from sale of common stock | $ 2,900,000 |  |  |  |  |  |  |
Subsequent Event [Member] | Common Stock [Member] | Canaccord Genuity LLC [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Common stock issued (in shares) | 536,070 |  |  |  |  |  |  |
Proceeds from sale of common stock | $ 1,500,000 |  |  |  |  |  |  |
Piramal Pharma Solutions, Inc. [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Master service agreement date |  | Jan. 08, 2021 |  |  |  |  |  |
Master services agreement initial term |  | 5 years |  |  |  |  |  |
Master services agreement terms, Description |  | The MSA has a term of five years and will automatically renew for successive one-year terms unless either party notifies the other no later than six months prior to the original term or any additional terms of its intention to not renew the MSA. The Company has the right to terminate the MSA for convenience upon thirty days’ prior written notice. |  |  |  |  |  |

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