Valuation Allowance for Deferred Taxes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at end of period	$ 487,745	$ 469,067
Valuation allowance for deferred taxes
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of period	469,067	375,301	433,781
Additions charged to costs and expenses	69,685	46,825	31,012
Additions/(Reductions) charged to other accounts	(39,065)	76,489	(77,954)
Reductions charged to costs and expenses	(11,942)	(29,548)	(11,538)
Balance at end of period	$ 487,745	$ 469,067	$ 375,301