Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 75,000	$ 64,113
Work in progress	22,762	16,425
Finished goods and products held for resale	51,400	44,402
Costs of unbilled projects	2,391	5,706
Reserves for excess and obsolete	(11,086)	(10,599)
Inventory, Net	$ 140,467	$ 120,047