| **Income Taxes (Details 3) - USD ($) $ in Millions** | Dec. 31, 2016 | Dec. 31, 2015 |
|------------------------------------------------------|---------------|---------------|
| **Deferred tax assets**                              |          |          |
| Deferred and refundable income taxes                 | $ 89          | $ 75          |
| **Deferred tax liabilities**                         |          |          |
| Deferred income taxes and other liabilities          | (939)         | (812)         |
| Deferred income taxes, net                           | $ (850)       | $ (737)       |

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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of deferred tax liability attributable to taxable temporary differences.
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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.
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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.
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