Accrued Liabilities (Details) (USD $)	3 Months Ended					5 Months Ended		12 Months Ended
	Oct. 31, 2012		Oct. 31, 2011		Apr. 30, 2011	Oct. 31, 2011		Oct. 31, 2012		Oct. 31, 2011
Accrued Liabilities, Current [Abstract]
Accrued Payroll and Employee Benefits	$ 3,907,000	[1]	$ 4,672,000	[1]		$ 4,672,000	[1]	$ 3,907,000	[1]	$ 4,672,000	[1]
Accrued Contract and Operating Costs	39,000	[2]	88,000	[2]		88,000	[2]	39,000	[2]	88,000	[2]
Product Warranty Accrual	2,317,000	[3]	1,134,000	[3]		1,134,000	[3]	2,317,000	[3]	1,134,000	[3]
Reserve for Service Agreement Costs	7,222,000	[4]	11,096,000	[4]		11,096,000	[4]	7,222,000	[4]	11,096,000	[4]
Reserve for Repair and Upgrade Program	4,753,000	[5]	7,949,000	[5]		7,949,000	[5]	4,753,000	[5]	7,949,000	[5]
Other Accrued Liabilities, Current	2,027,000	[6]	1,955,000	[6]		1,955,000	[6]	2,027,000	[6]	1,955,000	[6]
Accrued Liabilities, Current	20,265,000		26,894,000			26,894,000		20,265,000		26,894,000
Product Warranty Accrual, Warranties Issued								3,100,000		900,000
Product Warranty Accrual, Payment and Adjustments								1,900,000		500,000
Loss Reserve on Service Agreements	5,000,000		8,900,000			8,900,000		5,000,000		8,900,000
Reserve for Performance Guarantees	2,200,000		2,200,000			2,200,000		2,200,000		2,200,000
Charge for Repair and Upgrade	600,000		600,000		8,800,000
Value of Replacement Modules for Repair and Upgrade Charge					9,500,000
Other Module Value for Repair and Upgrade Charge					4,100,000
Estimated Fair Value of Upgraded Assets Deployed for Repair and Upgrade Program					4,800,000
Costs for Repair and Upgrades						2,900,000		3,700,000
Reduction in Repair and Upgrade Accrual						$ 500,000

[1] Balance relates to amounts owed to employees for compensation and benefits as of the end of the period.

[2] Balance includes estimated losses accrued on product sales contracts.

[3] Activity in the reserve for product warranty costs during the year ended October 31, 2012 and 2011 included additions for estimates of potential future warranty obligations of $3.1 million and $0.9 million, respectively, on contracts in the warranty period and reserve reductions related to actual warranty spend and reversals to income of $1.9 million and $0.5 million, respectively, as contracts progress through the warranty period or are beyond the warranty period.

[4] The Company provides for reserves on all SA agreements when the estimated future stack replacement and service costs exceed the remaining unrecognized contract value. Our reserve estimates are performed on a contract by contract basis and include cost assumptions based on what we anticipate the service requirements will be to fulfill obligations for each contract. As of October 31, 2012, our reserve on SA contracts totaled $5.0 million compared to $8.9 million as of October 31, 2011. If minimum output falls below the contract requirement, we may be subject to performance penalties or may be required to repair or replace the customer’s fuel cell stack. An estimate is not recorded for a potential performance guarantee liability until a performance issue has occurred on a particular power plant. At that point, the actual power plant’s output is compared against the minimum output guarantee and a reserve is recorded. The Company has provided a reserve for performance guarantees, which based on historical fleet performance totaled $2.2 million as of October 31, 2012 and 2011.

[5] During the second quarter of fiscal 2011, the Company incurred an obligation to repair and upgrade a select group of 1.2 megawatt (MW) fuel cell modules produced between 2007 and early 2009. The repair and upgrade obligation was based on events that occurred and knowledge obtained concerning the performance of this select group of modules during the second fiscal quarter of 2011 however, the formal agreement to begin the repair and upgrade program was not finalized until May 2011. The program commenced in the third quarter of 2011 and with the exception of providing replacement modules to POSCO, has concluded during fiscal year 2012. The Company recorded a charge of approximately $8.8 million during the quarter ended April 30, 2011 recorded as a cost of product sales and revenues on the consolidated statements of operations. The charge consisted of the costs associated with the replacement of modules of $9.5 million and the costs associated with the repair of other modules of $4.1 million, partially off-set by the estimated fair value at the end of the respective SA contract terms for upgraded assets being deployed in the program of approximately $4.8 million, which will be returned to the Company at the expiration of the respective LTSA agreements if the customer does not renew the SA agreement through at least the remaining useful life of the upgraded assets. For the remainder of fiscal 2011 since April 30, 2011, the Company incurred actual repair and upgrade costs of approximately $2.9 million and reduced its estimate for future repair costs under this program resulting in a benefit to cost of product sales and revenues of $0.5 million. For the year ended October 31, 2012, the Company incurred actual repair and upgrade costs of approximately $3.7 million and increased the reserve by $0.6 million during the fourth quarter of 2012 to adjust for the cost of modules which are expected to be provided to POSCO in accordance with the B1200 repair campaign when needed.

[6] Balance includes accrued sales, use and payroll taxes as well as estimated legal, professional and other expense estimates as of the end of the period.