Property, Plant, and Equipment, net (Schedule of Property, Plant, and Equipment) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Sep. 30, 2018
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 70,254	$ 46,359
Accumulated depreciation	(33,023)	(28,143)
Property, plant, and equipment, net	37,231	18,216
SDI land and building
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	12,890	0
Building and improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	257	0
Equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	41,170	36,625
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	1,109	1,109
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	3,526	2,928
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	2,560	2,049
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 8,742	$ 3,648