Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Income Tax Disclosure [Abstract] | ||
| NOL and credit carryforwards | $ 2,728 | $ 2,842 |
| Taxes related to risk management activities and derivatives | 38 | 53 |
| Reorganization items and impairments | 222 | 212 |
| Deferred tax assets before valuation allowance | 2,988 | 3,107 |
| Valuation allowance | (1,581) | (1,637) |
| Total deferred tax assets | 1,407 | 1,470 |
| Deferred tax liabilities: property, plant and equipment | (1,266) | (1,377) |
| Deferred Tax Liabilities, Other | (93) | (3) |
| Deferred Tax Liabilities, Gross | (1,359) | (1,380) |
| Net deferred tax asset (liability) | 48 | 90 |
| Deferred Tax Liabilities, Gross, Noncurrent | (14) | 0 |
| Deferred income tax asset, non-current | $ 62 | $ 90 |
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- Definition Amount of deferred tax liability attributable to taxable temporary differences. 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 capital 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 temporary differences from derivative instruments. 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 and 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 and carryforwards, classified as noncurrent. 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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- Definition Amount after 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 before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from estimated impairment losses. 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 Gross amount of noncurrent deferred tax liabilities, which result from applying the applicable tax rate to taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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