Property, Plant, and Equipment, net (Schedule of Property, Plant, and Equipment) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Sep. 30, 2018
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 52,459	$ 46,359
Accumulated depreciation	(31,364)	(28,143)
Property, plant, and equipment, net	21,095	18,216
Equipment
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	37,838	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	3,065	2,928
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	2,294	2,049
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant, and equipment, gross	$ 8,153	$ 3,648