Revenue - Narrative (Details) - Extended warranty contracts [Member] - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019	Oct. 31, 2019
Disaggregation of Revenue [Line Items]
Contract liabilities	$ 249		$ 249		$ 279
Revenue from Contract with Customer, Including Assessed Tax	$ 23	$ 27	$ 74	$ 85