Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2014	Apr. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 984	$ 822	$ 936	$ 874
Other comprehensive income (loss), net of income taxes:
Unrealized gains on available-for-sale debt securities	0	0	2	0
Unrealized gains on available-for-sale equity securities	(1)	0	(5)	3
Foreign currency translation gains (losses)	3	0	(5)	1
Total other comprehensive income (loss), net	2	0	(8)	4
Comprehensive income	$ 986	$ 822	$ 928	$ 878