Net Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	6 Months Ended
Apr. 30, 2020	Apr. 30, 2019	Apr. 30, 2020	Apr. 30, 2019
Numerator:
Net (loss) earnings	$ (821)	$ 419	$ (488)	$ 596
Denominator:
Weighted-average shares used to compute basic net EPS (in shares)	1,291	1,367	1,295	1,384
Dilutive effect of employee stock plans (in shares)		15		13
Weighted-average shares used to compute diluted net EPS (in shares)	1,291	1,382	1,295	1,397
Net (loss) earnings per share:
Basic (in dollars per share)	$ (0.64)	$ 0.31	$ (0.38)	$ 0.43
Diluted (in dollars per share)	$ (0.64)	$ 0.30	$ (0.38)	$ 0.43
Anti-dilutive weighted-average stock awards (in shares)	48	2	48	3

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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