Description of Business and Summary of Significant Accounting Policies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Apr. 30, 2014 Business_Unit	Apr. 30, 2013	Apr. 30, 2014 Business_Unit	Apr. 30, 2013
Composition of shares used in the computation of basic and diluted net income per share
Number of businesses discontinued	3		3
Numerator:
Net income from continuing operations	$ 984	$ 858	$ 890	$ 869
Net income (loss) from discontinued operations	0	(36)	46	5
Net income	$ 984	$ 822	$ 936	$ 874
Shares used in basic per share amounts:
Weighted average common shares outstanding	284	297	285	296
Shares used in diluted per share amounts:
Weighted average common shares outstanding	284	297	285	296
Dilutive common equivalent shares from stock options and restricted stock awards (shares)	6	7	6	7
Dilutive weighted average common shares outstanding	290	304	291	303
Basic and diluted net income per share:
Basic net income per share from continuing operations	$ 3.47	$ 2.89	$ 3.12	$ 2.93
Basic net income (loss) per share from discontinued operations	$ 0.00	$ (0.12)	$ 0.16	$ 0.02
Basic net income per share	$ 3.47	$ 2.77	$ 3.28	$ 2.95
Diluted net income per share from continuing operations	$ 3.39	$ 2.83	$ 3.06	$ 2.87
Diluted net income (loss) per share from discontinued operations	$ 0.00	$ (0.12)	$ 0.16	$ 0.02
Diluted net income per share	$ 3.39	$ 2.71	$ 3.22	$ 2.89
Weighted average stock options and restricted stock units excluded from computation due to anti-dilutive effect (shares)	0	3	3	3
Customer Concentration Risk [Member] | Sales Revenue, Services, Net [Member]
Basic and diluted net income per share:
Concentration Risk, Number of Customers	0	0	0	0
Line of Credit [Member] | Accounts Receivable [Member]
Basic and diluted net income per share:
Concentration Risk, Number of Customers	0	0	0	0