Inventories (Summary of Inventories) (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Sep. 30, 2017
Inventory Disclosure [Abstract]
Components, assemblies and parts	$ 90,588	$ 86,991
Customer projects in various stages of completion	32,978	30,225
Finished goods	9,932	10,512
Total inventories, net	$ 133,498	$ 127,728