Insurance - Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended	9 Months Ended
	Jul. 31, 2017	Apr. 30, 2017	Jul. 31, 2017	Jul. 31, 2016
Schedule of Other Liabilities [Line Items]
Self insurance retention amount per-claim	$ 1,000,000		$ 1,000,000
Insurance policy coverage, general and automobile liability losses	200,000,000		200,000,000
Insurance policy coverage, property damage	75,000,000		75,000,000
Change in reserves for insurance claims	12,300,000	$ 10,000,000	22,300,000	$ 31,800,000
Insurance reserve adjustment, amount less than prior year adjustment			9,500,000
Minimum
Schedule of Other Liabilities [Line Items]
Primary policy limit	1,000,000		1,000,000
Maximum
Schedule of Other Liabilities [Line Items]
Primary policy limit	5,000,000		5,000,000
Self insurance retention amount per-claim, medical plan	$ 400,000.0		$ 400,000.0