Estimated Useful Life of Definite-Lived Intangible Assets (Detail)	12 Months Ended
	Sep. 30, 2014
Completed technology | Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life	4 years
Completed technology | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life	10 years
Customer relationships | Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life	5 years
Customer relationships | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life	15 years
Trade names | Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life	1 year
Trade names | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated useful life	5 years