CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Aug. 31, 2013	Aug. 31, 2012
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued
Preferred stock, shares outstanding
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	237,732,562	232,069,203
Common stock, shares outstanding	203,164,870	206,028,577
Treasury stock, shares	34,567,692	26,040,626