Commitments And Contingencies (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Lease expense, excluding executory costs	$ 30.7	$ 22.1	$ 22.4
Contingent rent percentage	11.50%
Lease expiration date	2027
Optional renewal term in years	10
Number of optional renewal terms	3
Maximum [Member]
Annual base rent rate	11.00%
Minimum [Member]
Annual base rent rate	10.00%
Various Other [Member]
Amount outstanding in letters of credit	59.7
Employee Housing Bonds [Member]
Amount outstanding in letters of credit	53.4
Workers' Compensation and General Liability Related to Construction and Development Activities [Member]
Amount outstanding in letters of credit	4.3
Holland Creek Metropolitan District [Member]
Credit-enhanced bonds issued amount	8
Amount outstanding in letters of credit	8.1
Red Sky Ranch Metropolitan District [Member]
Other long-term liabilities	$ 1.8	$ 1.9
Estimated cessation date of capital improvement fee payment obligation	July 31, 2028