Warrants - (Details) - USD ($) $ / shares in Units, $ in Thousands						9 Months Ended
	Jun. 22, 2020	Mar. 05, 2020	Jan. 03, 2020	Feb. 05, 2019	Jan. 01, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Warrants
Number of Shares Issuable						52,704,735
Warrant liability reclassified to additional paid in capital					$ 3,448
Warrant, Down Round Feature, (Increase) Decrease in Equity, Amount						$ 303	$ 359
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)				7,557,142
Common stock issued				7,557,142
Series A Convertible Preferred Stock
Warrants
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)						1,421,801
Common stock issued						1,421,801
Series B Convertible Preferred Stock
Warrants
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)						1,137,442
Common stock issued						1,137,442
2017 Warrants
Warrants
Exercise price of warrant				$ 6.085		$ 1.055		$ 1.75
Class of Warrant or Right, Exercised						$ 220
Number of warrants or rights exercised.						208,254,000
2019 Warrants
Warrants
Number of Shares Issuable				7,557,142
Exercise price of warrant				$ 1.95
Class of Warrant or Right, Exercised						$ 128
Number of warrants or rights exercised.						65,700,000
January 2020 Warrants | Series A Convertible Preferred Stock
Warrants
Exercise price of warrant		$ 0.001
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)			1,421,801
Purchase price			$ 10.54
Warrant to purchase shares of common stock		14,413,902
Common stock issued			1,421,801
January 2020 Warrants | Series B Convertible Preferred Stock
Warrants
Exercise price of warrant		$ 2.11
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)			1,137,442
Purchase price			$ 10.55
Conversion of Stock, Shares Issued		11,531,133
Common stock issued			1,137,442
June 2020 Warrants
Warrants
Exercise price of warrant	$ 0.001
Warrant to purchase shares of common stock	2,250,000
June 2020 Warrants | Common Stock
Warrants
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)	20,250,000
Purchase price	$ 2.00
Common stock issued	20,250,000
1/23/2017
Warrants
Number of Shares Issuable						54,516
Exercise price of warrant						$ 0.01
11/14/2017
Warrants
Number of Shares Issuable						2,549,840
Exercise price of warrant						$ 1.055
2/5/2019
Warrants
Number of Shares Issuable						7,491,442
Exercise price of warrant						$ 1.95
3/5/2020
Warrants
Number of Shares Issuable						14,413,902
Exercise price of warrant						$ 0.001
3/5/2020
Warrants
Number of Shares Issuable						25,945,035
Exercise price of warrant						$ 2.11
6/22/2020
Warrants
Number of Shares Issuable						2,250,000
Exercise price of warrant						$ 0.001
Common Stock | June 2020 Warrants
Warrants
Issuance of Series A & B Convertible Preferred Stock, net of underwriting discounts (in shares)	20,250,000
Common stock issued	20,250,000