Stockholders' Equity - Share-Based Compensation Expense (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 382	$ 326	$ 281
Income tax benefit	(199)	(179)	(86)
Decrease in net income from continuing operations	183	147	192
Discontinued operations, share-based compensation expense
Decrease in net income per share from continuing operations:
Share based compensation expense for discontinued operations			3
Software and Software Development Costs
Decrease in net income per share from continuing operations:
Share-based compensation expense	$ 3	$ 7	$ 6
Share Based Compensation Expense
Decrease in net income per share from continuing operations:
Basic (in dollars per share)	$ 0.71	$ 0.57	$ 0.73
Diluted (in dollars per share)	$ 0.70	$ 0.56	$ 0.72
Cost of product revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 3	$ 0	$ 0
Cost of service and other revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	40	8	8
Selling and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	101	88	77
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	133	122	90
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	105	108	103
Total share-based compensation expense from continuing operations
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 382	$ 326	$ 278

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Earnings Per Share, Increase (Decrease), Basic

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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