Recently Completed Acquisitions - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Nov. 30, 2012 Entity	Sep. 21, 2012 Synta, Inc. Minimum	Sep. 05, 2012 Kirker Enterprises, Inc. Minimum
Business Acquisition [Line Items]
Expected annual sales		$ 40	$ 100
Number of acquisition completed	2
Business acquisition, preliminary fair value of goodwill	160.9
Business acquisition, preliminary fair value of other intangible assets	103.3
Business acquisition, preliminary fair value of contingent consideration	$ 63.5