Goodwill and Other Intangible Assets, Net - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Sep. 30, 2018
Intangible Assets
Amortization of customer relationships, patents, non-competes and other intangibles	$ 50	$ 131	$ 205	$ 395
Total intangible assets, Gross Amount	6,191		6,191		$ 10,221
Finite-lived intangible assets, Accumulated Amortization	(857)		(857)		(4,682)
Carrying Amount	5,334		5,334		5,539
Patents
Intangible Assets
Finite-Lived Intangible Assets, Gross					4,030
Finite-lived intangible assets, Accumulated Amortization					(3,977)
Finite-lived intangible assets, Carrying Amount					53
Customer relationships
Intangible Assets
Finite-Lived Intangible Assets, Gross	2,100		2,100		2,100
Finite-lived intangible assets, Accumulated Amortization	(682)		(682)		(574)
Finite-lived intangible assets, Carrying Amount	1,418		1,418		1,526
Other Intangible Assets
Intangible Assets
Finite-Lived Intangible Assets, Gross	291		291		291
Finite-lived intangible assets, Accumulated Amortization	(175)		(175)		(131)
Finite-lived intangible assets, Carrying Amount	116		116		160
Trademarks
Intangible Assets
Indefinite-lived intangible assets	$ 3,800		$ 3,800		$ 3,800