Insurance - Instruments Used to Collateralize Insurance Obligations (Details) - USD ($) $ in Millions	Jul. 31, 2019	Oct. 31, 2018
Letters Of Credit [Line Items]
Instruments used to collateralize insurance obligations	$ 235.2	$ 233.9
Standby letters of credit
Letters Of Credit [Line Items]
Instruments used to collateralize insurance obligations	143.5	144.1
Surety bonds
Letters Of Credit [Line Items]
Instruments used to collateralize insurance obligations	90.9	89.2
Restricted insurance deposits
Letters Of Credit [Line Items]
Instruments used to collateralize insurance obligations	$ 0.8	$ 0.6