Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2020	Oct. 31, 2019
Goodwill And Intangible Assets [Line Items]
Goodwill	$ 4,075	$ 4,075	$ 4,075
Intangible assets	20,615	20,615	21,264
Versa Acquisition [Member]
Goodwill And Intangible Assets [Line Items]
Goodwill	4,100	4,100	4,100
Intangible assets	20,600	20,600	21,300
Bridgeport Fuel Cell, LLC [Member]
Goodwill And Intangible Assets [Line Items]
Intangible assets	11,000	11,000	11,700
Intangible assets recorded during the period			$ 12,300
Amortization expenses	$ 300	$ 700