Related Party Transactions (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
Feb. 05, 2019	Dec. 31, 2019
Related Party Transactions
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)	7,557,142
Price per share (in dollars per share)	$ 1.75
Number of warrants issued per common stock	1
Issuance of common stock (value)	$ 12,122	$ 12,122
Underwriters' exercise
Related Party Transactions
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)	985,714
2019 Warrants
Related Party Transactions
Exercise price (per warrant)	$ 1.95
Warrant expiring period	7 years

Number of warrants issued on purchase of one common stock.

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Exercise price per share or per unit of warrants or rights outstanding.

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Per share or per unit amount of equity securities issued.

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Number of new stock issued during the period.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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