INCOME TAXES (Details) - USD ($) $ in Millions	3 Months Ended
Jan. 31, 2019	Jan. 31, 2018
Income Tax Disclosure
Provision (benefit) for income taxes	$ (256)	$ 553
Effective income tax rate	(103.20%)	237.30%
Discrete tax expense (benefit)	$ (299)
Excess tax benefit from stock based compensation	$ (4)	$ (11)
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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