Goodwill and Intangible Assets - Weighted Average Amortization Period by Intangible Asset Class (Detail)	Sep. 30, 2012 Year
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	7.4
Trademarks and patents
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	9.2
Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	6.2
Covenant not-to-compete
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	3.8
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted Average Amortization Period	9.4