Income Taxes - Reconciliation of the Federal Statutory Income Tax Rate to the 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] | |||
| U.S. Statutory rate | 34.00% | 34.00% | 34.00% |
| State income taxes, net of federal benefit | 0.37% | 0.88% | 2.00% |
| Stock-based compensation | (30.40%) | (23.74%) | 0.65% |
| Change in valuation allowance | (2.59%) | (4.26%) | (7.91%) |
| R&D credit, net of reserve | (1.43%) | (1.75%) | (2.97%) |
| Expiration of net operating losses | 2.76% | 4.51% | 1.17% |
| Reassessment of prior year APIC benefit | (3.11%) | ||
| Effect of U.S tax law change | 25.55% | ||
| Other | 0.92% | 0.07% | (2.50%) |
| Effective income tax rate | 29.18% | 9.71% | 21.33% |
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- Definition Effective income tax rate reconciliation net operating loss expiration. No definition available.
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- Definition Effective income tax rate reconciliation nondeductible expense share based compensation expense (benefit). No definition available.
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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 other adjustments. 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 revisions of previously reported income tax expense. 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit). 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 research tax credit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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