Income Taxes (Summary Of Differences Between The Financial Statement And Tax Bases Of Assets And Liabilities) (Details) - USD ($) $ in Thousands |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|---|
| Deferred Tax Assets: | |||
| Basis difference in fixed assets | $ 46,929 | $ 89,016 | |
| Foreign tax credit carryforward | 48,071 | 50,339 | |
| Alternative minimum tax credit carryover | 1,349 | 1,349 | |
| U.S. federal net operating losses | 22,490 | 30,230 | |
| Foreign net operating losses | 26,371 | 25,543 | |
| Asset retirement obligations | 4,234 | 6,514 | |
| Basis difference in receivables | 1,331 | 1,824 | |
| Other | 3,690 | 6,952 | |
| Total deferred tax assets | 154,465 | 211,767 | |
| Valuation allowance | (153,205) | $ (211,767) | $ (210,700) |
| Net deferred tax assets | $ 1,260 |
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- Definition Deferred Tax Assets, Receivables No definition available.
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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 and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local 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 foreign operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. 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 from property, plant, and equipment. No definition available.
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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 foreign 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 temporary differences from asset retirement obligations. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset. 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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