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Stock Warrants - Stock Warrants (Details) - USD ($)						1 Months Ended		3 Months Ended		12 Months Ended
Stock Warrants - Stock Warrants (Details) - USD ($)	Nov. 16, 2020	Oct. 15, 2018	Oct. 15, 2018	Oct. 10, 2018	Nov. 18, 2016	Jan. 31, 2021	Oct. 31, 2018	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Nov. 15, 2020	Nov. 06, 2020	Nov. 05, 2020	Dec. 31, 2019	Dec. 26, 2017
Equity, Class of Treasury Stock
Proceeds from "at the market" stock issuance		$ 18,600,000	$ 18,600,000
Stock Issued During Period, Shares, New Issues						78,700,000
Exercise price per warrant	$ 0.69	$ 1.38	$ 1.38				$ 1.38				$ 1.38	$ 0.69	$ 1.38
Preferred Stock, Par or Stated Value Per Share	$ 0.0010							$ 1,000		$ 1,000
Effect of Warrant exercise price adjustment										$ 880,000
Percentage of issue of the public offering							120.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	0
Cash proceeds from exercise of warrants								$ 8,042,000	$ 0
Warrants Not Settleable in Cash, Fair Value Disclosure															$ 9,000,000
Proceeds from Issuance of Common Stock						$ 65,000,000		$ 65,960,000	$ 0
Series B Preferred Stock [Member]
Equity, Class of Treasury Stock
Preferred Stock, Par or Stated Value Per Share		$ 1,000	$ 1,000
Stock Issued During Period, Value, Issued for Services		$ 1,000	$ 1,000
Preferred Stock Conversion Price Per Share		$ 1.15	$ 1.15
Conversion of Stock, Shares Converted		13,672,173	13,672,173					3,973	1,073
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		13,672,173	13,672,173
IPO [Member]
Equity, Class of Treasury Stock
Stock Issued During Period, Shares, New Issues					714,286
Shares Issued, Price Per Share					$ 35.00
Class of Warrant or Right, Number of Securities Called by Warrants or Rights					1,428,571
Warrants Not Settleable in Cash, Fair Value Disclosure					$ 15,700,000									$ 100,000,000
IPO [Member] \| Series B Warrants [Member]
Equity, Class of Treasury Stock
Exercise price per warrant					$ 60.20
Over-Allotment Option [Member]
Equity, Class of Treasury Stock
Stock Issued During Period, Shares, New Issues	2,428,825			2,428,825
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	2,428,825			2,428,825
Issue of warrants to purchase common stock				1,807,826
Underwritten Public Offering [Member] \| October 2018 Warrants [Member]
Equity, Class of Treasury Stock
Warrant Term		5 years
Series A Warrants [Member] \| IPO [Member] \| Series A Warrants [Member]
Equity, Class of Treasury Stock
Exercise price per warrant					$ 50.05
Warrant [Member]
Equity, Class of Treasury Stock
Class of Warrant or Right, Number of Securities Called by Warrants or Rights								11,655,747
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Warrants Exercisable Number															714
Warrant [Member] \| Series B Preferred Stock [Member]
Equity, Class of Treasury Stock
Conversion of Stock, Shares Converted		13,672,173