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Capitalized Costs Related to Oil and Natural Gas (Detail) (USD $)
In Millions, unless otherwise specified |
Dec. 31, 2012
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Dec. 31, 2011
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Dec. 31, 2010
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| Net capitalized cost: | |||
| Proved oil and natural gas properties and equipment | $ 6,551.5 | $ 5,775.4 | $ 5,130.9 |
| Unproved oil and natural gas properties and equipment | 143.0 | 183.6 | 94.7 |
| Accumulated depreciation, depletion and amortization related to oil, NGLs and natural gas activities | (4,640.8) | (4,307.1) | (4,009.9) |
| Net capitalized costs related to producing activities | $ 2,053.7 | $ 1,651.9 | $ 1,215.7 |
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- Definition
Amount of accumulated depreciation, depletion, amortization and valuation allowance relating to oil and gas producing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Capitalized costs of proved properties that include fee ownership or a lease, concession, or other interest representing the right to extract oil or gas subject to such terms as may be imposed by the conveyance of that interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Capitalized costs of unproven properties that include fee ownership or a lease, concession, or other interest representing the right to extract oil or gas subject to such terms as may be imposed by the conveyance of that interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Net amount of capitalized costs relating to oil and gas producing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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