INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2019	Apr. 30, 2018	Apr. 30, 2019	Apr. 30, 2018
Income Tax Disclosure
Provision (benefit) for income taxes	$ 36	$ 22	$ (220)	$ 575
Effective income tax rate	16.50%	9.70%	(47.20%)	125.00%
Discrete tax expense (benefit)			$ (299)
Excess tax benefit from stock based compensation	$ (3)	$ (7)	$ (7)	$ (18)
U.S. Tax Cuts and Jobs Act of 2017
Income Tax Disclosure
Discrete tax expense related to enactment of the Tax Act				$ 533

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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