COMMON STOCK (Details 2) (Stock Option [Member], USD $)	12 Months Ended
	Jul. 31, 2011	Jul. 31, 2010	Jul. 31, 2009
Stock Option [Member]
Stock Options
Weighted average fair value at grant date	$ 15.78	$ 10.44	$ 6.79
Valuation assumptions:
Expected dividend yield	1.90%	2.00%	1.80%
Expected volatility	36.80%	35.20%	31.90%
Expected life (years)	5	5	5
Risk-free interest rate	1.80%	2.20%	1.80%