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Reconciliation of Asset Retirement Obligations Liability (Detail) (USD $)
In Thousands, unless otherwise specified |
12 Months Ended | ||
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Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2010
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| Asset Retirement Obligations [Line Items] | |||
| Asset retirement obligations, beginning of period | $ 393,880 | $ 391,316 | |
| Liabilities settled | (112,827) | (59,958) | |
| Accretion of discount | 20,055 | 29,771 | 25,685 |
| Disposition of properties | (3,993) | ||
| Liabilities assumed through acquisition | 31,664 | 8,194 | |
| Liabilities incurred | 1,815 | 565 | |
| Asset retirement obligations, end of period | 384,053 | 393,880 | 391,316 |
| Less current portion | 92,630 | 138,185 | |
| Long-term | 291,423 | 255,695 | |
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Hurricane Ike
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| Asset Retirement Obligations [Line Items] | |||
| Revisions of estimated liabilities | (20,616) | 4,744 | |
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All Other
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| Asset Retirement Obligations [Line Items] | |||
| Revisions of estimated liabilities | $ 74,075 | $ 19,248 | |
| X | ||||||||||
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- Definition
The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of asset retirement obligations incurred during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Asset Retirement Obligations, Disposition Of Properties No definition available.
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- Definition
Asset Retirement Obligations, Liabilities Assumed Through Acquisition No definition available.
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- Details
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