Other Balance Sheet Information - Summary of Inventories (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Sep. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Raw materials and purchased parts	$ 60,883	$ 62,441
Work-in-process	16,488	21,563
Finished goods	20,786	16,615
Inventory, net	98,157	100,619
Reserves for excess and obsolete inventory	$ 24,900	$ 23,800