Insurance - Instruments Used to Collateralize Insurance Obligations (Details) - USD ($) $ in Millions	Jul. 31, 2017	Oct. 31, 2016
Letters Of Credit [Line Items]
Instruments used to collateralize insurance obligations	$ 189.9	$ 186.7
Standby letters of credit
Letters Of Credit [Line Items]
Instruments used to collateralize insurance obligations	118.8	118.3
Surety bonds
Letters Of Credit [Line Items]
Instruments used to collateralize insurance obligations	59.9	57.2
Restricted insurance deposits
Letters Of Credit [Line Items]
Instruments used to collateralize insurance obligations	$ 11.2	$ 11.2