Prepaid expenses (Detail) - USD ($) $ in Thousands	Oct. 31, 2017	Oct. 31, 2016
Prepaid Expense, Current [Abstract]
Parts and supplies	$ 25,293	$ 23,022
Prepaid insurance	6,691	6,084
Other prepaid expenses	6,636	5,453
Prepaid expenses, total	$ 38,620	$ 34,559