Insurance - Narrative (Details) - USD ($) |
3 Months Ended | 6 Months Ended | 9 Months Ended | |
|---|---|---|---|---|
Jul. 31, 2018 |
Apr. 30, 2018 |
Jul. 31, 2018 |
Jul. 31, 2017 |
|
| 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 | 6,000,000 | $ 4,000,000 | 10,000,000 | $ 22,300,000 |
| Insurance reserve adjustment, amount less than prior year adjustment | (12,300,000) | |||
| 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 | ||