FAIR VALUE MEASUREMENTS, Fair value of assets and liabilities measured on a recurring basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Apr. 30, 2020	Oct. 31, 2019
Assets Short - term
Cash equivalents (money market funds)	$ 682	$ 784
Derivative instruments (foreign exchange contracts)	8	12
Assets, Long-term
Trading securities	27	30
Other investments	22	25
Total assets measured at fair value	739	851
Liabilities, Short-term
Derivative instruments (foreign exchange contracts)	7	6
Liabilities Long-term
Deferred compensation liability	27	30
Total liabilities measured at fair value	34	36
Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets Short - term
Cash equivalents (money market funds)	682	784
Derivative instruments (foreign exchange contracts)	0	0
Assets, Long-term
Trading securities	27	30
Other investments	0	0
Total assets measured at fair value	709	814
Liabilities, Short-term
Derivative instruments (foreign exchange contracts)	0	0
Liabilities Long-term
Deferred compensation liability	0	0
Total liabilities measured at fair value	0	0
Significant Other Observable Inputs (Level 2)
Assets Short - term
Cash equivalents (money market funds)	0	0
Derivative instruments (foreign exchange contracts)	8	12
Assets, Long-term
Trading securities	0	0
Other investments	22	25
Total assets measured at fair value	30	37
Liabilities, Short-term
Derivative instruments (foreign exchange contracts)	7	6
Liabilities Long-term
Deferred compensation liability	27	30
Total liabilities measured at fair value	34	36
Significant Unobservable Inputs (Level 3)
Assets Short - term
Cash equivalents (money market funds)	0	0
Derivative instruments (foreign exchange contracts)	0	0
Assets, Long-term
Trading securities	0	0
Other investments	0	0
Total assets measured at fair value	0	0
Liabilities, Short-term
Derivative instruments (foreign exchange contracts)	0	0
Liabilities Long-term
Deferred compensation liability	0	0
Total liabilities measured at fair value	$ 0	$ 0