Income Taxes - Income Tax Benefit from Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Income Tax Provision Accompanying Consolidated Statements of Operation
Loss before income tax benefit	$ (13,140)	$ (13,333)
Income tax benefit at U.S. federal statutory rates	(4,599)	(4,667)
Tax effect of:
Foreign rate differential	120	254
State and local income taxes	(6)	(42)
Impact of tax law changes	(103)	(338)
Federal tax credits	(252)	(572)
Valuation allowance	5,720	3,309
Other	189	58
Income tax provision (benefit)	$ 1,069	$ (1,998)

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit).

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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