Stockholders' Equity and Warrant Liabilities - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands									1 Months Ended	3 Months Ended		5 Months Ended		7 Months Ended	12 Months Ended
	Jun. 11, 2021	Dec. 07, 2020	Dec. 04, 2020	Jun. 16, 2020	Jan. 08, 2020	Oct. 04, 2019	Feb. 21, 2019	May 03, 2017	Oct. 31, 2020	Jan. 31, 2021	Jan. 31, 2020	Oct. 31, 2021	Oct. 31, 2020	Jun. 10, 2021	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2019	Apr. 08, 2021	Apr. 07, 2021	May 11, 2020	May 10, 2020	May 08, 2020	Nov. 22, 2019	May 08, 2019	Jul. 12, 2016
Stockholders' Equity Note
Number of incremental common stock shares approved																		162,500,000				112,500,000
Common stock, shares authorized									337,500,000			500,000,000	337,500,000		500,000,000	337,500,000		500,000,000.0	337,500,000	337,500,000	225,000,000.0			225,000,000
Sale of stock, price per share			$ 7.95		$ 2.29				$ 2.00		$ 1.59		$ 2.00			$ 2.00	$ 0.24
Class of warrants or rights purchase											9,396,320
Class of warrants or rights exercised											12,000,000
Expected volatility		117.02%			103.70%						104.90%					114.15%	96.00%
Risk-free interest rate		0.70%			1.81%						1.45%					0.64%	1.63%
Class of warrants or rights charge					$ 23,700					$ 16,000	$ 10,500					$ 200
Reclassification of estimated fair value of warrant liability to additional paid in capital		$ 21,200			$ 26,000
Common stock, shares issued									294,706,758			366,618,693	294,706,758		366,618,693	294,706,758
Change in fair value of common stock warrant liability															$ 15,974	$ 37,086
Expected life (in years)																	8 years
Class of warrants or rights issued value																	$ 3,900
Other Noncurrent Liabilities [Member]
Stockholders' Equity Note
Fair value of warrants outstanding									$ 5,200				$ 5,200			$ 5,200
Exchange Agreement [Member]
Stockholders' Equity Note
Common stock issued to warrant holders							500,000
Series C Warrants [Member]
Stockholders' Equity Note
Class of warrant or right, issued and outstanding									964,128			950,102	964,128		950,102	964,128	964,128
Series A Warrants [Member]
Stockholders' Equity Note
Class of warrants or rights issued																									640,000
Class of Warrant or Right, Exercise Price of Warrants or Rights																									$ 69.96
Series A Warrants [Member] | Exchange Agreement [Member]
Stockholders' Equity Note
Change in fair value of common stock warrant liability																	$ 300
Fair value of the shares at the date of the Exchange Agreement																	$ 3,500
Common Stock [Member]
Stockholders' Equity Note
Stock issued during period shares new issues															69,074,573	86,307,932	119,128,677
Common Stock [Member] | Series C Warrants [Member]
Stockholders' Equity Note
Stock issued during period shares new issues															14,026	0	0
Net proceeds from common stock and warrants															$ 300
Second Funding Warrants [Member] | Warrant [Member]
Stockholders' Equity Note
Percentage of warrants vesting																	100.00%
Orion Energy Partners Investment Agent, LLC Credit Facility [Member]
Stockholders' Equity Note
Class of warrant or right, issued and outstanding									2,700,000				2,700,000			2,700,000	6,000,000
Orion Energy Partners Investment Agent, LLC Credit Facility [Member] | Exercise Price 0.242 [Member]
Stockholders' Equity Note
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 0.242
Class of warrants or rights purchase		2,700,000
Class of warrants or rights issued value		$ 600
Orion Credit Agreement [Member] | Initial Funding Warrants [Member]
Stockholders' Equity Note
Class of warrants or rights issued																	6,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights																	$ 0.310
Orion Credit Agreement [Member] | Second Funding Warrants [Member]
Stockholders' Equity Note
Class of warrants or rights issued																							14,000,000
Orion Credit Agreement [Member] | Second Funding Warrants [Member] | Exercise Price 0.242 [Member]
Stockholders' Equity Note
Class of warrants or rights issued																							8,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights																							$ 0.242
Orion Credit Agreement [Member] | Second Funding Warrants [Member] | Exercise Price 0.620 [Member]
Stockholders' Equity Note
Class of warrants or rights issued																							6,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights																							$ 0.620
Underwriting Agreement [Member]
Stockholders' Equity Note
Stock issued to underwriters			19,822,219
Sale of stock, number of shares issued in transaction			14,696,320
Sale of stock, price per share			$ 6.50
Stock issued during period shares new issues			25,000,000						50,000,000.0
Common stock issuance, net of fees			$ 162,500
Underwriting discounts and commissions			$ 0.2275
Net proceeds from issuance of common stock			$ 156,400
Proceeds from Issuance Initial Public Offering									$ 105,100
Net proceeds from issuance of public offering.									$ 98,300
Underwriting Agreement [Member] | Maximum [Member]
Stockholders' Equity Note
Option to purchase additional common stock shares			5,177,781
At Market Issuance Sales Agreement [Member] | Jefferies LLC [Member] | Common Stock [Member]
Stockholders' Equity Note
Stock issued during period shares new issues												44,100,000	28,300,000	0
Common stock issuance, net of fees													$ 72,300
Net proceeds from issuance of common stock												$ 369,700
Aggregate Offering Price	$ 500,000
Payments of Stock Issuance Costs													$ 2,200
Percentage Of Sales Commission	2.00%			3.00%
Average Sale Of Stock Price Per Share									$ 2.55			$ 8.56	$ 2.55		$ 8.56	$ 2.55
Gross Proceeds From Issuance Of Common Stock												$ 377,200	$ 70,100
Payments of commissions and offering expenses	$ 7,500
Sale agreement, common stock, value, available for issuance												$ 122,800			$ 122,800
Common stock, shares reserved for issuance														0
At Market Issuance Sales Agreement [Member] | B Riley F B R Inc [Member]
Stockholders' Equity Note
Percentage Of Sales Commission						3.00%
Common stock, shares reserved for issuance						27,900,000
Reserve for issuance of common stock upon exercise of warrants shares																	20,000,000.0
At Market Issuance Sales Agreement [Member] | B Riley F B R Inc [Member] | Common Stock [Member]
Stockholders' Equity Note
Stock issued during period shares new issues																7,900,000	10,100,000
Common stock issuance, net of fees																$ 3,600	$ 3,000
Net proceeds from issuance of common stock																3,500	2,900
Payments of Stock Issuance Costs																$ 100	$ 100
Average Sale Of Stock Price Per Share									$ 0.46				$ 0.46			$ 0.46
At Market Issuance Sales Agreement [Member] | Maximum [Member] | Jefferies LLC [Member] | Common Stock [Member]
Stockholders' Equity Note
Aggregate Offering Price	$ 500,000			$ 75,000
At Market Issuance Sales Agreement [Member] | Maximum [Member] | B Riley F B R Inc [Member]
Stockholders' Equity Note
Aggregate Offering Price						$ 38,000
Common stock, shares reserved for issuance																	7,900,000
Common stock, shares issued																	18,000,000.0
Underwritten Public Offering [Member] | Series C Warrants [Member]
Stockholders' Equity Note
Class of warrants or rights issued								1,000,000
Class of warrant or right term								5 years
Warrants issued, price per share								$ 19.20