Aggregate dividends paid during the period for each share of common stock outstanding.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Stockholders' Equity - Stock Repurchase Programs, Treasury Shares, and Dividends on Common Stock (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Feb. 24, 2020	Jan. 31, 2020	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock repurchased (in shares)					1.0
Common stock repurchased, value		$ 5	$ 139	$ 177	$ 278	$ 278
Stock repurchase program, remaining authorized repurchase amount		$ 2,400	2,400		$ 2,400
Common stock, dividends, per share, cash paid (in dollars per share)					$ 1.06
Dividends declared			$ (140)	$ (124)	$ (281)	$ (250)
Cash dividends declared per common share (in dollars per share)			$ 0.53	$ 0.47	$ 1.06	$ 0.94
Subsequent event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash dividends declared per common share (in dollars per share)	$ 0.53
Retained Earnings
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividends declared			$ (140)	$ (124)	$ (281)	$ (250)