Taxes on Earnings - Schedule of Deferred Tax Asset Valuation Allowance and Changes (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018
Movement in Valuation Allowances and Reserves
Balance at beginning of year	$ 7,930	$ 7,906	$ 8,807
Income tax (benefit) expense	74	(339)	(897)
Other comprehensive loss (income), currency translation and charges to other accounts	(28)	363	(4)
Balance at end of year	$ 7,976	$ 7,930	$ 7,906