Document and Entity Information - shares	6 Months Ended
	Apr. 30, 2016	Jun. 06, 2016
Document and Entity Information
Entity Registrant Name	FUELCELL ENERGY INC
Entity Central Index Key	0000886128
Document Type	10-Q
Document Period End Date	Apr. 30, 2016
Amendment Flag	false
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--10-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		31,386,019