Property, Plant, and Equipment, Net (Property, Plant, and Equipment - Net) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Property, Plant, and Equipment, Net
Land and Land Improvements	$ 87,696	$ 79,311
Buildings and improvements	527,704	372,160
Leasehold improvements	15,213	16,907
Machinery and production equipment	484,315	365,040
Computer equipment and software	117,984	118,154
Office furniture and equipment	29,344	20,939
Other	18,969	18,325
Construction in progress	88,909	252,763
Property, Plant and Equipment, Gross, Total	1,370,134	1,243,599
Less accumulated depreciation	(493,784)	(487,499)
Property, Plant and Equipment, Net, Total	876,350	756,100
Depreciation expense	41,550	45,994	$ 43,773
Capitalized interest	$ 5,455	$ 8,995	$ 7,282