Accumulated Other Comprehensive Income Comprehensive Net Income (Details) (USD $) In Millions, unless otherwise specified	Jul. 31, 2013	Jul. 31, 2012
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ 2	$ 6
Accumulated Other Comprehensive Income (Loss), Net of Tax	20	25
Debt Securities [Member]
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	0	1
Equity Securities [Member]
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	$ 18	$ 18