CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Feb. 28, 2019	Aug. 31, 2018
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 14,456	$ 15,181
Property, plant and equipment, accumulated depreciation	3,860,332	3,646,945
Intangible assets, accumulated amortization	$ 321,965	$ 307,178
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	259,739,745	257,130,145
Common stock, shares outstanding	152,878,329	164,588,172
Treasury stock, shares	106,861,416	92,541,973

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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