REVENUE - Revenue by End Markets (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Net revenue	$ 1,548	$ 1,357
Pharmaceutical and Biopharmaceutical
Net revenue	521	423
Chemical and Energy
Net revenue	328	312
Diagnostics and Clinical
Net revenue	216	194
Food
Net revenue	162	130
Academia and Government
Net revenue	142	141
Environmental and Forensics
Net revenue	$ 179	$ 157