Capital Assets (Property and Equipment) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 269,749	$ 262,575
Less: Accumulated depreciation	(175,408)	(162,645)
Total property and equipment, net	94,341	99,930
Land and improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	2,866	2,867
Buildings and improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	60,704	60,340
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	203,293	196,621
Assets held under capital leases
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 2,886	$ 2,747