Stockholders' Equity - Narrative (Details) - Share Repurchase program - USD ($) shares in Millions, $ in Millions	3 Months Ended	12 Months Ended
Jan. 31, 2019	Oct. 31, 2018
Equity, Class of Treasury Stock [Line Items]
Common stock retired (in shares)	55.0	2.4
Open share repurchases during period (in shares)	1.2
Repurchases of common stock recorded as a reduction to stockholders' equity	$ 795
Remaining authorized repurchase amount	$ 3,900

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
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Period Type:	duration