Alternative Minimum Tax

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- Definition

Discontinued Operation, Deferred Income Tax Expense (Benefit), Discontinued Operations

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- Definition

Operating Loss Carryforward, Portion Not Subject Limitation

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- Definition

Operating Loss Carryforward, Portion Subject Limitation

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No definition available.

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- Definition

Unrecognized Tax Benefits, Increase (Decrease) Resulting from Current Period Tax Positions

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No definition available.

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- Definition

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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- Definition

Amount of tax expense (benefit) on gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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- Definition

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

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- Definition

A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.

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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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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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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.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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Income and other Taxes (Narrative) (Details) - USD ($)	3 Months Ended								12 Months Ended
Income and other Taxes (Narrative) (Details) - USD ($)	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Operating Loss Carryforwards [Line Items]
Income tax expense	$ (32,000)	$ (19,000)	$ 8,000	$ (120,000)	$ 8,000	$ (175,000)	$ 155,000	$ (2,000)	$ (163,000)	$ (14,000)	$ 2,191,000	$ 24,600,000
Deferred tax assets											24,600,000
Alternative minimum tax											600,000
Deferred income tax benefit from discontinued operations											24,100,000
Income tax (expense) benefit, discontinued operations									$ 0	$ 24,000	$ (26,500,000)
Effective tax rate									(1.90%)	(0.50%)	(49.10%)
Adjustments based on tax positions related to the current year									$ 131,000	$ 0
Decrease in unrecognized tax benefits										100,000	$ 200,000
Income tax penalties and interest accrued	300,000				$ 300,000				300,000	300,000
Operating loss carryforward portion subject limitation	226,500,000								226,500,000
Operating loss carryforward portion not subject to limitation	198,400,000								198,400,000
Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	424,900,000								424,900,000
Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	2,300,000								2,300,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	52,500,000								52,500,000
Continuing Operations [Member]
Operating Loss Carryforwards [Line Items]
Decrease in unrecognized tax benefits										112,800	100,000
Discontinued Operations [Member]
Operating Loss Carryforwards [Line Items]
Decrease in unrecognized tax benefits										12,000	100,000
Income tax credits and adjustments									0	$ 400,000	$ 200,000
Foreign Income and Research And Development Credit [Member]
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	$ 3,200,000								$ 3,200,000