Income Taxes (Schedule Of Roll Forward Of Valuation Allowance For Deferred Income Tax Assets) (Details) - USD ($) $ in Thousands |
12 Months Ended | ||||
|---|---|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Income Taxes [Abstract] | |||||
| Valuation Allowance, Balance at beginning of period | $ 67,662 | $ 64,486 | $ 15,628 | ||
| Charged (Credited) to Costs and Expenses | 3,166 | 3,176 | 48,858 | ||
| Other Adjustments | [1] | (25,017) | |||
| Valuation Allowance, Balance at end of period | $ 45,811 | $ 67,662 | $ 64,486 | ||
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- Definition Deferred Tax Assets Valuation Allowance, Charged (Credited) To Costs And Expenses No definition available.
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- Definition Deferred Tax Assets, Valuation Allowance, Other Adjustments No definition available.
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| X | ||||||||||
- 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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- References No definition available.
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