Summary of AMS Amounts Included in Discontinued Operations (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Aug. 31, 2014	Aug. 31, 2013	Aug. 31, 2012
Discontinued Operations and Disposal Groups [Abstract]
Net revenue	$ 586,652	$ 1,087,401	$ 1,011,236
Income from discontinued operations, before tax	26,694	58,950	72,351
Income tax expense	6,140	8,342	9,945
Income from discontinued operations, net of tax	20,554	50,608	62,406
Gain on sale of discontinued operations, before tax	230,878
Income tax expense	7,579
Gain on sale of discontinued operations, net of tax	223,299
Discontinued operations, net of tax	$ 243,853	$ 50,608	$ 62,406