Income Taxes (Details Textual) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) affiliate	Dec. 31, 2017 USD ($)
Income Tax Examination [Line Items]
Number of foreign affiliates subject to tax in Estonia \| affiliate	1
Tax rate for earnings and profits as they are generated	0.00%
Remeasurement at new rate, percent	21.00%
Operating loss carryforwards		$ 41.7
Change in ownership percent		50.00%
Ownership change (greater than)		5.00%
Minimum
Income Tax Examination [Line Items]
Tax rate for earnings and profits that are distributed to shareholders	14.00%
Tax rate applied to dividends	14.00%
Maximum
Income Tax Examination [Line Items]
Tax rate for earnings and profits that are distributed to shareholders	20.00%
Tax rate applied to dividends	20.00%
Not Subject to Limitations \| Subsequent To Change Date In 2010
Income Tax Examination [Line Items]
Operating loss carryforwards		$ 23.1
Subject to Limitations \| Minimum
Income Tax Examination [Line Items]
Operating loss carryforwards		1.0
Subject to Limitations \| Maximum
Income Tax Examination [Line Items]
Operating loss carryforwards		$ 2.3
Alternative Minimum Tax Carryover
Income Tax Examination [Line Items]
Credit receivable	$ 0.1

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Number Of Foreign Affiliates

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Stockholder Ownership

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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 deduction for dividend.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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

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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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