Segment Information - Narrative (Details) $ in Millions	9 Months Ended	12 Months Ended
	Jul. 31, 2017 USD ($) business_acquired segment	Oct. 31, 2016 USD ($) segment
Segment Reporting [Abstract]
Number of segments | segment	4	4
Advanced payments from advanced royalty payment arrangements | $	$ 439	$ 3,700
Term of arrangements	5 years
Number of businesses acquired | business_acquired	5