Repurchase of Common Stock (Narrative) (Details) - February 2019 Share Repurchase Program [Member] - USD ($) $ in Billions	Oct. 31, 2020	Feb. 23, 2019
Stock Repurchases [Line Items]
Stock Repurchase Program, Authorized Amount	$ 3.0	$ 3.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 1.9

[Line Items] for Stock Repurchases [Table] details the shares (value and share count) and average price of stock purchased during the presented periods.

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