Income Taxes (Narrative) (Details) - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended |
|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
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| Income Taxes [Abstract] | ||
| Statutory income tax benefit | 21.00% | 35.00% |
| Tax Cuts and Jobs Act of 2017, Valuation Allowance, Federal | $ 4,512 | |
| Tax Cuts and Jobs Act of 2017, Valuation Allowance, State, If Recognized | 400 | |
| Gross deferred tax asset | 50,732 | |
| Valuation allowance | 45,811 | |
| Net deferred tax asset | 4,921 | |
| Deferred tax liabilities, gross | 8,587 | |
| Net operating loss carryforwards for U.S. federal income tax purposes | 156,598 | |
| Research and experimentation credit carryforwards | 3,452 | |
| Alternative minimum tax credit carryforwards | $ 0 |
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- Definition Tax Cuts and Jobs Act of 2017, Valuation Allowance, Federal No definition available.
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- Definition Tax Cuts and Jobs Act of 2017, Valuation Allowance, State, If Recognized No definition available.
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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