Income Taxes - Reconciliation Between the Tax Provision Computed at the Federal Statutory Income Tax Rate and Actual Effective Income Tax Rate (Details) |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Effective Income Tax Rate Continuing Operations Tax Rate Reconciliation [Abstract] | |||
| Federal tax at statutory rate | 34.00% | 34.00% | 34.00% |
| Warrant valuation | 7.00% | 29.00% | |
| Stock compensation and other permanent differences | 6.00% | (1.00%) | |
| Tax credits | (4.00%) | 2.00% | (14.00%) |
| Impact of 2017 Tax Act on change in deferred | 128.00% | ||
| Section 382 limitations | 868.00% | ||
| Valuation allowance | (1022.00%) | (43.00%) | (48.00%) |
| Total | 10.00% | 0.00% | 0.00% |
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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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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- Definition 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 valuation allowance for deferred tax assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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 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://www.xbrl.org/2003/role/presentationRef
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- Definition 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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Effective income tax rate reconciliation stock compensation and other permanent differences percent. No definition available.
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- Definition 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 warrant valuation. No definition available.
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