Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Nov. 30, 2011	Aug. 31, 2011
Condensed Consolidated Balance Sheets [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 2,995	$ 4,788
Property, plant and equipment, accumulated depreciation	1,380,963	1,363,481
Intangible assets, accumulated amortization	$ 129,849	$ 128,467
Preferred stock, par value	$ 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	$ 0.001	$ 0.001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	230,427,378	224,653,990
Common stock, shares outstanding	207,612,936	203,416,503
Treasury shares	22,814,442	21,237,487