Provision for Income Taxes - Additional Information (Detail) - USD ($) |
12 Months Ended | |
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Sep. 30, 2018 |
Sep. 30, 2017 |
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| Income Tax Contingency [Line Items] | ||
| Deferred tax assets, gross | $ 3,840,000 | $ 5,781,000 |
| Fuel tax credits | 300,000 | 300,000 |
| Goodwill expected to be deductible to tax purposes | 14,900,000 | 15,300,000 |
| Income tax benefit related to tax act | 4,600,000 | |
| Permanent tax benefit | 2,282,000 | 686,000 |
| Amount resulting from deduction fair market value of options over exercise price | 1,400,000 | |
| Unrecognized tax benefits | 0 | 0 |
| State | ||
| Income Tax Contingency [Line Items] | ||
| Operating loss carryforwards | $ 38,300,000 | $ 52,500,000 |
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- Definition Effective Income Tax Rate Reconciliation, Deduction, Excess Market Value Of Options Exercised, Amount No definition available.
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- Definition Tax Cuts And Jobs Act Of 2017, Change In Tax Rate, Deferred Tax Liability, Income Tax (Expense) Benefit No definition available.
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- Definition The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition 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 deductions. Including, but not limited to, extraterritorial income exclusion deduction, qualified production activity deduction, dividend deduction, deduction for dividend paid to employee stock ownership plan, Medicare prescription drug benefit subsidy deduction, and other deductions. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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