Insurance - Instruments Used to Collateralize Insurance Obligations (Details) - USD ($) $ in Millions |
Jul. 31, 2018 |
Oct. 31, 2017 |
|---|---|---|
| Letters Of Credit [Line Items] | ||
| Instruments used to collateralize insurance obligations | $ 236.3 | $ 226.3 |
| Standby letters of credit | ||
| Letters Of Credit [Line Items] | ||
| Instruments used to collateralize insurance obligations | 146.7 | 137.6 |
| Surety bonds | ||
| Letters Of Credit [Line Items] | ||
| Instruments used to collateralize insurance obligations | 89.0 | 77.5 |
| Restricted insurance deposits | ||
| Letters Of Credit [Line Items] | ||
| Instruments used to collateralize insurance obligations | $ 0.6 | $ 11.2 |