Goodwill and Other Intangible Assets, net (Details) (USD $)	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2011
Goodwill [Line Items]
Goodwill, Impaired, Accumulated Impairment Loss	$ 0
Goodwill [Roll Forward]
Goodwill, beginning of period	627,805,000	380,332,000
Acquisitions	1,454,000	243,924,000
Purchase price adjustments	1,540,000
Purchase accounting adjustments	5,902,000	1,035,000
Foreign currency translation adjustment	(1,210,000)	2,514,000
Goodwill, end of period	635,491,000	627,805,000
MRB [Member]
Goodwill [Roll Forward]
Goodwill, beginning of period	464,646,000	230,198,000
Acquisitions	1,454,000	232,341,000
Purchase price adjustments	1,540,000
Purchase accounting adjustments	5,361,000	1,086,000
Foreign currency translation adjustment	(1,047,000)	1,021,000
Goodwill, end of period	471,954,000	464,646,000
APB [Member]
Goodwill [Roll Forward]
Goodwill, beginning of period	163,159,000	150,134,000
Acquisitions	0	11,583,000
Purchase price adjustments	0
Purchase accounting adjustments	541,000	(51,000)
Foreign currency translation adjustment	(163,000)	1,493,000
Goodwill, end of period	$ 163,537,000	$ 163,159,000