Property, Plant, and Equipment, Net (Property, Plant, and Equipment - Net) (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Property, Plant, and Equipment, Net
Land and Land Improvements	$ 87,294		$ 87,696
Buildings and improvements	525,710		527,704
Leasehold improvements	14,662		15,213
Machinery and production equipment	481,041		484,315
Computer equipment and software	122,418		117,984
Office furniture and equipment	29,133		29,344
Other	19,121		18,969
Construction in progress	92,516		88,909
Property, Plant and Equipment, Gross, Total	1,371,895		1,370,134
Less accumulated depreciation	(494,818)		(493,784)
Property, Plant and Equipment, Net, Total	877,077		$ 876,350
Depreciation expense	12,455	$ 10,116
Capitalized interest	$ 472	$ 1,873