Schedule of Accrued Liabilities (Parenthetical) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Oct. 31, 2020
Schedule Of Accrued Liabilities [Line Items]
Product warranty accrual, payment and adjustments	$ 10	$ 20
Loss reserve on service agreements	4,500		$ 5,500
Deferred Director Compensation	800		100
Bridgeport Fuel Cell Project [Member]
Schedule Of Accrued Liabilities [Line Items]
Reserve for performance guarantees	$ 1,300		$ 1,400