Income Taxes - Income Tax Benefit from Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Income (loss) before income tax benefit	$ 8,980	$ (8,207)
Income tax provision (benefit) at U.S. federal statutory rates	1,886	(1,723)
Tax effect of:
Foreign rate differential	0	1,698
State and local income taxes	20	14
Federal tax credits	(135)	(144)
Valuation allowance	(2,025)	(556)
Other	43	10
Income tax benefit	$ (211)	$ (701)

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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 foreign income tax expense (benefit).

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