Other Balance Sheet Information - Product Warranty and Retrofit Activity on Gross Basis (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance at beginning of year	$ 7,329	$ 7,438	$ 8,195
Adjustments for acquisitions and divestitures	1,187	7	698
Accruals for warranties during the year	10,111	13,751	11,299
Costs incurred	(11,278)	(13,867)	(12,754)
Balance at end of year	$ 7,349	$ 7,329	$ 7,438