Income Taxes (Narrative) (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended |
|---|---|---|
Mar. 31, 2018 |
Dec. 31, 2017 |
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| Income Taxes [Abstract] | ||
| Alternative minimum tax credit | $ 1.4 | |
| Valuation allowance | $ 1.3 | |
| U.S. corporate income tax rate | 21.00% | 35.00% |
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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 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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| X | ||||||||||
- References No definition available.
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