Asset Retirement Obligations (Narrative) (Detail) $ in Millions |
9 Months Ended |
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Sep. 30, 2015
USD ($)
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| Maximum [Member] | |
| Asset Retirement Obligation [Line Items] | |
| Estimate of increase costs | $ 15.0 |
| Minimum [Member] | |
| Asset Retirement Obligation [Line Items] | |
| Estimate of increase costs | $ 10.0 |
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- Definition Asset Retirement Obligation, Estimate Of Increase Costs No definition available.
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- Definition Asset Retirement Obligation [Line Items] No definition available.
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- Details
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- Details
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