Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Property and equipment	$ 113,600	$ 109,860
Less: accumulated depreciation and amortization	(75,178)	(71,652)
Total	$ 38,422	$ 38,208