4. Common Stock Offerings (Details Narrative) - USD ($)	1 Months Ended						3 Months Ended	5 Months Ended	6 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	May 31, 2020	Mar. 31, 2020	Feb. 28, 2020	Jan. 31, 2020	Jun. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	May 24, 2021	Jan. 28, 2021	Sep. 09, 2020	Mar. 16, 2020	Feb. 19, 2020	Feb. 13, 2020
Business Acquisition [Line Items]
Cash received from stock sale							$ 64,476,000		$ 97,957,000	$ 8,850,000
December 2020 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued	1,112,219
Cash received from stock sale	$ 10,900,000
September 42020 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued		8,865,000
Cash received from stock sale									$ 6,400,000
Warrant terms and provisions									The Company also issued to the investors warrants to purchase up to 6,648,750 shares of common stock in a concurrent private placement (the "September 2020 Warrants"). The September 2020 Warrants have an exercise price of $0.84 per share of common stock, became exercisable beginning on March 9, 2021 and will expire on March 9, 2026.
Shares Issued, Price Per Share													$ 0.79
May 112020 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued			300,000
Consulting expense								$ 431,000
May 242021 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued									22,258,066
Cash received from stock sale									$ 64,500,000
Shares Issued, Price Per Share											$ 3.10
Offering proceeds used to partially repay certain convertible promissory notes									$ 7,300,000
January 282021 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued									17,530,488
Cash received from stock sale									$ 33,500,000
Shares Issued, Price Per Share												$ 2.05
Offering proceeds used to partially repay certain convertible promissory notes									$ 3,800,000
March 162020 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued				7,500,000
Cash received from stock sale				$ 4,000,000.0
Shares Issued, Price Per Share														$ 0.60
February 132020 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued					6,666,667
Cash received from stock sale					$ 4,800,000
Shares Issued, Price Per Share																$ 0.75
February 192020 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued					999,999
Shares Issued, Price Per Share															$ 0.75
January 22020 [Member]
Business Acquisition [Line Items]
Number of shares of common stock issued						1,809,845
January 242019 [Member]
Business Acquisition [Line Items]
Warrant terms and provisions									Pursuant to the Purchase Agreement, STI (i) issued and sold to the Investors an aggregate of 2,374,672 shares of STI’s common stock which converted pursuant to the exchange ratio in the Merger into the right to receive 1,829,407 shares of the Company’s common stock and (ii) issued warrants representing the right to acquire 1,463,519 shares of common stock at a price per share of $4.15, subject to adjustment as provided therein (the “Series A Warrants”), most recently adjusted to a price per share of $0.2957 per share, and additional warrants initially representing the right to acquire no shares of common stock at a price per share of $0.001, subject to adjustment as provided therein (the “Series B Warrants” together with the Series A Warrants, the “Investor Warrants”), for aggregate gross proceeds of $18.0 million, or $16.5 million net of financing fees. The terms of the Investor Warrants included certain provisions that could result in adjustments to both the number of warrants issued and the exercise price of each warrant, which resulted in the warrants being classified as a liability upon issuance (see Note 7). The Investor Warrants were recorded at fair value of $21.5 million upon issuance and given that the liability exceeded the proceeds received, a loss of $5.0 million was recognized.
March 72019 [Member]
Business Acquisition [Line Items]
Warrant terms and provisions									On March 7, 2019, the Company entered into Amendment Agreements (collectively, the “Amendment Agreements”) with each Investor amending: (i) the Purchase Agreement, (ii) the Series A Warrants, and (iii) the Series B Warrants. The Amendment Agreements, among other things, fixed the aggregate number of shares of common stock issued and issuable pursuant to the Series A Warrants at 3,629,023 (none of which were exercised as of March 7, 2019). The terms of the Investor Warrants continue to include certain provisions that could result in a future adjustment to the exercise price of the Investor Warrants and accordingly, they continue to be classified as a liability after the Amendment Agreements.
Series A Warrants unexercised							300,000		300,000