Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2013	Jan. 31, 2012
Income Taxes [Abstract]
Effective tax rate	28.30%	29.60%	28.90%	27.30%
Adjustment from settlements of tax audits		$ 4.3		$ 4.3
Unrecognized tax benefits	18.5		18.5
Accrued interest and penalties on unrecognized tax benefits	1.2		1.2
Statute of limitations period, average, years			5 years
Maximum possible reduction in amount of unrecognized tax benefits			1.1
Unrecognized tax benefits potential expiration period			12 months
Unrecognized tax benefits in dispute with various taxing authorities	$ 0.2		$ 0.2