Fair Value Measurements - Financial Instruments Measured on Nonrecurring Basis (Details) - USD ($) $ in Millions	Jul. 31, 2017	Oct. 31, 2016
Impaired finance receivables with specific loss reserves [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 20	$ 15
Specific loss reserves on impaired finance receivables [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Specific loss reserve	$ (9)	$ (8)