Acquisition - Summary of fair values of assets acquired and liabilities assumed as part of acquisition (Detail) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012	Aug. 31, 2011	Jan. 10, 2011
Business Acquisition [Line Items]
Cash			$ 15,863
Accounts receivable			41,618
Inventories			60,740
Other current assets			13,257
Property, plant and equipment, net			54,392
Other long-term assets			12,296
Intangible assets			214,120
Total identifiable assets acquired excluding goodwill			412,286
Current liabilities			45,287
Long-term liabilities			78,980
Total liabilities assumed			124,267
Net identifiable assets acquired excluding goodwill			288,019
Goodwill	577,874	592,051	330,377
Net assets acquired			$ 618,396