Income Taxes - Income Tax Benefit from Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Income Tax Provision Accompanying Consolidated Statements of Operation
Loss before income tax benefit	$ (7,531)	$ (13,140)
Income tax benefit at U.S. federal statutory rates	(1,582)	(4,599)
Tax effect of:
Foreign rate differential	694	120
State and local income taxes	(25)	(6)
Impact of tax law changes	820	(103)
Federal tax credits	(1,573)	(252)
Valuation allowance	1,243	5,720
Prior year tax adjustments	(211)	34
Other	273	155
Income tax provision (benefit)	$ (361)	$ 1,069

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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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