Nature of Business, Basis of Presentation and Significant Accounting Policies - Additional Information (Details)			1 Months Ended	3 Months Ended								12 Months Ended
		Aug. 29, 2017 USD ($) MW	Jun. 30, 2017 MW	Oct. 31, 2018 USD ($)	Jul. 31, 2018 USD ($)	Apr. 30, 2018 USD ($)	Jan. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Jul. 31, 2017 USD ($)	Apr. 30, 2017 USD ($)	Jan. 31, 2017 USD ($)	Oct. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Oct. 31, 2016 USD ($)
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Restricted Cash and Cash Equivalents				$ 40,900,000				$ 38,200,000				$ 40,900,000	$ 38,200,000
Restricted cash and cash equivalents - long-term				35,142,000				33,526,000				35,142,000	33,526,000
Letters of Credit Outstanding, Amount				3,800,000				2,900,000				$ 3,800,000	2,900,000
Letter of Credit Date of Expiration												Aug. 01, 2025
Customer Advances, Current				3,000				3,000,000				$ 3,000	3,000,000
Short-term project assets				0				0				0	0
Impairment charges												0	0	$ 0
Impairment on project asset												500,000	0	0
Revenue				17,884,000	$ 12,110,000	$ 20,830,000	$ 38,613,000	47,889,000	$ 10,358,000	$ 20,417,000	$ 17,002,000	$ 89,437,000	95,666,000	108,252,000
Excess service agreements term												5 years
Extended Product Warranty Description												We warranty our products for a specific period of time against manufacturing or performance defects. Our U.S. warranty is limited to a term generally 15 months after shipment or 12 months after acceptance of our products.
Product Warranty Accrual	[1]			147,000				348,000				$ 147,000	348,000
Reserve for Performance Guarantees				1,100,000				2,200,000				1,100,000	2,200,000
Loss reserve on service agreements				900,000				1,100,000				900,000	1,100,000
Long-term stack residual value	[2]			1,206,000				987,000				1,206,000	987,000
Future license fees to be paid												$ 18,000,000
License agreement amortization period												15 years
Reduced royalty percentage												3.00%
Foreign Currency Transaction Gain (Loss), Unrealized												$ 300,000	(700,000)	$ 300,000
Net operating loss carryforwards				202,643,000				282,022,000				202,643,000	282,022,000
Accumulated deficit				(990,867,000)				(943,533,000)				(990,867,000)	$ (943,533,000)
ASU 2016-09 [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Net impact on equity												0
Net operating loss carryforwards				7,800,000								7,800,000
Unrecognized net operating loss carryforwards offset by valuation allowance				7,800,000								7,800,000
ASU 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Minimum [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Accumulated deficit				7,000								7,000
ASU 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Maximum [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Accumulated deficit				10,000								$ 10,000
Sales Revenue Net [Member] | Customer Concentration Risk [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Significant customer revenue percentage												84.00%	78.00%	75.00%
Stack Technology Transfer and License Agreement [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Upfront License Fee				10,000,000								$ 10,000,000
Service and License Fee Revenues [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
License Fee and Royalty Income												2,100,000	$ 2,700,000	$ 6,200,000
Dominion Bridgeport FuelCell Park [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Restricted cash and cash equivalents - long-term				$ 15,000,000				15,000,000				$ 15,000,000	$ 15,000,000
Restricted cash and cash equivalents - long-term service agreement												15 years
Dominion Bridgeport FuelCell Park [Member] | Sales Revenue Net [Member] | Customer Concentration Risk [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Significant customer revenue percentage												3.00%	11.00%	6.00%
Hanyang Industrial Development Co., Ltd [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Number of MW awarded | MW			20
Contract to sell fuel cell plants | MW		20
Project represented value of contract		$ 70,000,000
Hanyang Industrial Development Co., Ltd [Member] | Electricity [Member]
Nature of Business, Basis of Presentation and Significant Accounting Policies [Line items]
Revenue								$ 39,000,000				$ 31,000,000

[1] Activity in the accrued product warranty costs for the years ended October 31, 2018 and 2017 included additions for estimates of future warranty obligations of $0.4 million and $0.6 million, respectively, on contracts in the warranty period and reductions related to actual warranty spend of $0.6 million and $0.8 million, respectively, as contracts progress through the warranty period or are beyond the warranty period.

[2] Relates to estimated residual value for module exchanges performed under the Company’s service agreements where the useful life extends beyond the contractual term of the service agreement and the Company obtains title for the module from the customer upon expiration or non-renewal of the service agreement. If the Company does not obtain rights to title from the customer, the full cost of the module is expensed at the time of the module exchange.