Property, Plant, and Equipment (Schedule of Property Plant and Equipment, Net) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	$ 1,651,390	$ 1,672,227
Less accumulated depreciation	(653,975)	(613,452)
Property, plant, and equipment, net	997,415	1,058,775
Land and Land Improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	83,095	94,976
Building and Building Improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	551,540	587,541
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	18,610	17,446
Machinery and Production Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	776,884	731,159
Computer Equipment and Software [Member]
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	123,903	124,201
Office Furniture and Equipment [Member]
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	41,177	39,934
Other [Member]
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	19,814	19,346
Construction in Progress [Member]
Property Plant And Equipment [Line Items]
Property, plant, and equipment, gross	$ 36,367	$ 57,624