Goodwill and Other Intangible Assets - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Nov. 30, 2012
Product Rights [Line Items]
Impairment of goodwill	$ 0

Loss recognized during the period that results from the write-down of goodwill after comparing the implied fair value of reporting unit goodwill with the carrying amount of that goodwill. Goodwill is assessed at least annually for impairment.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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+ Details