Schedule of Accrued Liabilities (Parenthetical) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Oct. 31, 2019
Schedule Of Accrued Liabilities [Line Items]
Product warranty accrual, payment and adjustments	$ 20	$ 40
Loss reserve on service agreements	3,300		$ 3,300
Bridgeport Fuel Cell Project [Member]
Schedule Of Accrued Liabilities [Line Items]
Reserve for performance guarantees	$ 300		$ 800