Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Jun. 30, 2017
Property, Plant and Equipment
Property, plant and equipment gross	$ 364,370	$ 352,010
Accumulated depreciation	(202,558)	(192,280)
Land	16,336	16,336
Property, plant and equipment, net	178,148	176,066
Building and Facilities
Property, Plant and Equipment
Property, plant and equipment gross	108,999	108,682
Machinery and Equipment
Property, Plant and Equipment
Property, plant and equipment gross	212,180	201,236
Equipment under Capital Leases | Northlake, Texas
Property, Plant and Equipment
Property, plant and equipment gross	7,516	7,540
Capitalized Software Costs | Northlake, Texas
Property, Plant and Equipment
Property, plant and equipment gross	23,063	21,794
Office furniture and equipment
Property, Plant and Equipment
Property, plant and equipment gross	$ 12,612	$ 12,758