INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Oct. 31, 2018
Income Tax Disclosure
Provision for income taxes	$ 553	$ 25
Effective income tax rate	237.30%	13.00%
Net Discrete Tax Expense (Benefit)		$ (2)
Excess tax benefits from share-based compensation	$ 11
U.S. Tax Cuts and Jobs Act of 2017
Income Tax Disclosure
Discrete tax expense (benefit)	533
Net transition tax	480
Estimated provision associated with the impact of decreased U.S. corporate tax rate	53
Provisional income tax expense related to one-time transition tax	643
Income tax benefit due to reversal of deferred tax liability	$ (163)
Pension Settlement Gain
Income Tax Disclosure
Discrete tax expense (benefit)		11
Settlement with Taxing Authority-Italy
Income Tax Disclosure
Discrete tax expense (benefit)		$ (7)
Forecast
Income Tax Disclosure
Effective income tax rate			23.00%