Goodwill (Details) (USD $)	3 Months Ended
	Nov. 30, 2011
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 627,805,000
Purchase accounting adjustments	142,000
Foreign currency translation adjustment	(5,565,000)
Goodwill, end of period	622,382,000
Goodwill, Impaired, Accumulated Impairment Loss	0
Metal Recycling Business [Member]
Goodwill [Roll Forward]
Goodwill, beginning of period	464,646,000
Purchase accounting adjustments	142,000
Foreign currency translation adjustment	(4,808,000)
Goodwill, end of period	459,980,000
Auto Parts Business [Member]
Goodwill [Roll Forward]
Goodwill, beginning of period	163,159,000
Purchase accounting adjustments	0
Foreign currency translation adjustment	(757,000)
Goodwill, end of period	$ 162,402,000