Unrecognized tax benefits percentage reductions resulting from lapse of applicable statute of limitations.

No definition available.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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

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Percentage 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 changes in the income tax rates.

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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.

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No definition available.

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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 domestic income tax settlement.

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- Definition

Amount of undistributed earnings of foreign subsidiaries intended to be permanently reinvested outside the country of domicile.

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Income Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Income Tax Contingency [Line Items]
Blended tax rate		24.50%
Effective tax rate		7.00%	44.00%	13.00%
Tax expense		$ 500
Undistributed earnings of foreign subsidiaries		21,100
Valuation allowance related to deferred tax assets		$ 9,597	$ 8,767
Decrease in unrecognized tax benefits due to expiration of certain federal statutes of limitations		22.00%
R&D Tax Credit
Income Tax Contingency [Line Items]
Retroactive tax benefit	$ 800		$ 900