Segment Information (Detail 4) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Oct. 31, 2019	Jul. 31, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2018	Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2018	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Segment Reporting Information
Net revenue	$ 7,215	$ 7,217	$ 7,150	$ 7,553	$ 7,946	$ 7,764	$ 7,468	$ 7,674	$ 29,135	$ 30,852	$ 28,871
Net property, plant and equipment:
Property, plant and equipment	6,054				6,138				6,054	6,138
U.S.
Segment Reporting Information
Net revenue									9,582	10,192	10,022
Net property, plant and equipment:
Property, plant and equipment	2,894				2,813				2,894	2,813
Americas excluding U.S.
Segment Reporting Information
Net revenue									1,922	2,135	2,067
Total Americas
Segment Reporting Information
Net revenue									11,504	12,327	12,089
Europe, Middle East and Africa
Segment Reporting Information
Net revenue									10,828	11,295	10,024
Asia Pacific and Japan
Segment Reporting Information
Net revenue									6,803	7,230	$ 6,758
Other countries
Net property, plant and equipment:
Property, plant and equipment	$ 3,160				$ 3,325				$ 3,160	$ 3,325