Commitments and Contingencies (Narrative) (Details)			1 Months Ended			12 Months Ended
	Jan. 06, 2017 USD ($)	Sep. 23, 2014 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2012 USD ($)	Sep. 30, 2017 USD ($) building	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Loss Contingencies [Line Items]
Minimum lease payments, 2018						$ 800,000
Minimum lease payments, 2019						800,000
Minimum lease payments, 2020						800,000
Minimum lease payments, 2021						600,000
Minimum lease payments, 2022						1,300,000
Rent expense						$ 1,400,000	$ 1,400,000	$ 1,300,000
Fair value assumptions, credit adjusted risk-free rate, range minimal amount						1.20%
Fair value assumptions, credit adjusted risk-free rate, range maximum amount						4.20%
Accretion expense						$ 65,000	100,000	100,000
Reduction in ARO						45,000	300,000
Payments to terminate lease agreement							200,000
Asset retirement obligation						1,638,000	1,618,000
Business combination, indemnification assets, range of outcomes, value					$ 3,400,000.0
Business combination, indemnification duration, period taken into account for					2 years
Gain on settlement						0	0	$ 442,000
Sumitomo Electric Industries, LTD [Member]
Loss Contingencies [Line Items]
Loss contingency, damages sought		$ 47,500,000
Gain on settlement							3,400,000
Discontinued Operations, Disposed of by Sale [Member]
Loss Contingencies [Line Items]
Payments to terminate lease agreement				$ 200,000
Discontinued Operations, Disposed of by Sale [Member] | Sumitomo Electric Industries, LTD [Member]
Loss Contingencies [Line Items]
Gain on settlement							3,800,000
Write off of loss accrual							400,000
Settled Litigation [Member] | Sumitomo Electric Industries, LTD [Member]
Loss Contingencies [Line Items]
Loss contingency, proceeds			$ 1,900,000
Litigation settlement, amount received from SEI							2,600,000
Settled Litigation [Member] | Mirasol Class Action [Member]
Loss Contingencies [Line Items]
Litigation settlement, awarded to other party	$ 300,000
Settlement agreement						300,000
Provision accrual						$ 200,000
Settled Litigation [Member] | Mirasol Wrongful Termination [Member]
Loss Contingencies [Line Items]
Litigation settlement, awarded to other party	$ 50,000
Buildings [Member] | Property Subject to Operating Lease [Member]
Loss Contingencies [Line Items]
Number of leased buildings | building						6
Leases retroactively effective | building						4
Lease term (in years)						3 years
Operating lease, term extension, option to extend (in years)						3 years
Property in Alhambra, California [Member]
Loss Contingencies [Line Items]
Asset retirement obligation						$ 1,600,000	1,500,000
Property in Beijing, China [Member]
Loss Contingencies [Line Items]
Asset retirement obligation						$ 50,000	$ 48,000