Income Taxes - Schedule of Components of Deferred Income Tax Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Current deferred income taxes:
Gross assets	$ 0	$ 3,978
Gross liabilities and valuation allowance	0	(439)
Net current deferred income tax asset	0	3,539
Noncurrent deferred income taxes:
Gross assets	22,480	18,559
Gross liabilities and valuation allowance	(16,543)	(18,330)
Net noncurrent deferred income tax asset (liability)	5,937	229
Net deferred income tax asset	$ 5,937	$ 3,768

Deferred income tax assets liabilities net current.

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Deferred income tax assets liabilities net noncurrent.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards classified as current.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences and carryforwards, classified as noncurrent.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount of deferred tax liability attributable to taxable temporary differences classified as current.

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Gross amount of noncurrent deferred tax liabilities, which result from applying the applicable tax rate to taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax.

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