Restructuring and Other Charges - Other charges (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2016
Restructuring and Related Activities [Abstract]
Other restructuring costs	$ 33	$ 135	$ 30

Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Period Type:	duration