Stock Compensation Plan (Schedule Of Share Based Compensation Restricted Stock Units Activity) (Details) (Restricted Stock Units (RSUs) [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Jul. 31, 2012
Restricted Stock Units (RSUs) [Member]
Awards, outstanding beginning balance (in shares)	408
Awards, granted (in shares)	180
Awards, vested (in shares)	(234)
Awards, forfeited (in shares)	(36)
Awards, outstanding ending balance (in shares)	318
Weighted-average grant-date fair value, outstanding beginning balance (in dollars per share)	$ 33.47
Weighted-average grant-date fair value, granted (in dollars per share)	$ 38.15
Weighted-average grant-date fair value, vested (in dollars per share)	$ 39.31
Weighted-average grant-date fair value, forfeited (in dollars per share)	$ 36.38
Weighted-average grant-date fair value, outstanding ending balance (in dollars per share)	$ 37.82