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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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