Amortization Expense Associated with Intangible Assets (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Amortization expense of intangible assets	[1]	$ 3,599	$ 3,019	$ 10,046	$ 8,940
Cost of revenues
Finite-Lived Intangible Assets [Line Items]
Amortization expense of intangible assets		1,919	1,880	5,656	5,502
Selling, general and administrative expenses
Finite-Lived Intangible Assets [Line Items]
Amortization expense of intangible assets		$ 1,680	$ 1,139	$ 4,390	$ 3,438

[1] Cost of revenues and selling, general and administrative expenses exclude the amortization of intangible assets. See Note 5 to the condensed consolidated financial statements.