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v3.20.4

Subsequent Events (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Subsequent Event [Line Items] |  |  |  |
Issuance of common stock in connection with at market offering, net of issuance costs |  | $ 4,075,000 | $ 19,295,000 | $ 86,017,000
Scenario Forecast [Member] | Equity Investment |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Net proceeds from sale of shares held in BARDI | $ 1,594,000 |  |  |
Scenario Forecast [Member] | 2020 Sales Agreement |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Issuance of common stock in connection with at market offering, net of issuance costs (in shares) | 7,948,505 |  |  |
Issuance of common stock in connection with at market offering, net of issuance costs | $ 16,234,000 |  |  |

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