Stock-based Compensation (Schedule Of Stock Option Activity) (Details) $ / shares in Units, shares in Thousands, $ in Millions	6 Months Ended
	Jan. 31, 2016 USD ($) $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Beginning of year, Options | shares	74
Granted, Options | shares	711
Exercised, Options | shares	(74)
Terminated, Options | shares	0
End of year, Options | shares	711
Exercisable at end of period, Options | shares	0
Beginning of period, Weighted-Average Exercise Price | $ / shares	$ 29.91
Granted, Weighted-Average Exercise Price | $ / shares	50.21
Exercised, Weighted-Average Exercise Price | $ / shares	29.91
Terminated, Weighted-Average Exercise Price | $ / shares	0.00
End of period, Weighted-Average Exercise Price | $ / shares	50.21
Exercisable at end of period, Weighted-Average Exercise Price | $ / shares	$ 0.00
Outstanding at end of period, Weighted-Average Remaining Contractual Life (In years)	9 years 8 months
Exercisable at end of period, Weighted-Average Remaining Contractual Life (In years)	0 years
Outstanding at end of period, Aggregate Intrinsic Value | $	$ 4
Exercisable at end of period, Aggregate Intrinsic Value | $	$ 0