CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Feb. 28, 2017	Aug. 31, 2016
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 12,635	$ 11,094
Property, plant and equipment, accumulated depreciation	2,904,556	2,721,972
Intangible assets, accumulated amortization	$ 249,618	$ 232,618
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	252,553,308	249,763,699
Common stock, shares outstanding	182,349,673	186,998,472
Treasury stock, shares	70,203,635	62,765,227