Other Balance Sheet Information - Additional Information (Detail) (USD $)	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Valuation and Qualifying Accounts Disclosure [Line Items]
Inventory Valuation Reserves	$ 26,000,000	$ 24,200,000
Inventory Valuation Reserve
Valuation and Qualifying Accounts Disclosure [Line Items]
Charges/credits to reserves for excess and obsolete inventory	6,900,000	5,400,000	4,300,000
Reduction in reserves for excess and obsolete inventory	$ 5,100,000	$ 4,300,000	$ 5,800,000