Warrants - Additional Information (Details) - USD ($) $ in Thousands			12 Months Ended
	Jan. 16, 2018	Dec. 27, 2016	Sep. 30, 2020	Sep. 30, 2019
Class Of Warrant Or Right [Line Items]
Stock based compensation expense			$ 86	$ 142
Series B Convertible Preferred Stock Warrants
Class Of Warrant Or Right [Line Items]
Number of common shares into which each warrant may be exchanged			5
Warrants additional extended expiration period	2 years
Stock based compensation expense			$ 462	$ 128
Series B Convertible Preferred Warrants Expires on September 10, 2017
Class Of Warrant Or Right [Line Items]
Number of warrants outstanding		10,914
Expiration date		Sep. 10, 2017
Series B Convertible Preferred Warrants Expires on December 11, 2017
Class Of Warrant Or Right [Line Items]
Number of warrants outstanding		12,383
Expiration date		Dec. 11, 2017
Series B Convertible Preferred Warrants Expires on March 27, 2018
Class Of Warrant Or Right [Line Items]
Number of warrants outstanding		54,396
Expiration date		Mar. 27, 2018
Series B Convertible Preferred Warrants Expires on March 28, 2018
Class Of Warrant Or Right [Line Items]
Number of warrants outstanding		17,857
Expiration date		Mar. 28, 2018
Series B Convertible Preferred Warrants Expires on December 3, 2019
Class Of Warrant Or Right [Line Items]
Number of warrants outstanding			22,479
Expiration date			Dec. 03, 2019