Property, Plant, and Equipment, net (Tables)

12 Months Ended

Sep. 30, 2018

Property, Plant and Equipment [Abstract]

Schedule of Property, Plant and Equipment

Our property, plant, and equipment are recorded at cost. Plant and equipment are depreciated on a straight-line basis over the following estimated useful lives of the assets: 

Description	Estimated Useful Life
Equipment	three to ten years
Furniture and fixtures	five years
Computer hardware and software	five to seven years
Leasehold improvements	three to six years

The components of property, plant, and equipment, net consisted of the following:

	As of September 30,
(in thousands)	2018			2017
Equipment	$	36,625		$	31,507
Furniture and fixtures	1,109			1,109
Computer hardware and software	2,928			2,974
Leasehold improvements	2,049			2,330
Construction in progress	3,648			4,539
Property, plant, and equipment, gross	$	46,359		42,459
Accumulated depreciation	(28,143		)	(25,824		)
Property, plant, and equipment, net	$	18,216		$	16,635