Estimated Fair Value of Derivative Contracts (Detail) (USD $)
In Thousands, unless otherwise specified |
Mar. 31, 2013
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Dec. 31, 2012
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Prepaid And Other Assets
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Derivatives, Fair Value [Line Items] | ||
Fair value of commodity derivative contracts | $ 867 | |
Accrued Liabilities
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Derivatives, Fair Value [Line Items] | ||
Fair value of commodity derivative contracts | 6,938 | 6,355 |
Other Liabilities Noncurrent
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Derivatives, Fair Value [Line Items] | ||
Fair value of commodity derivative contracts | $ 2,427 | $ 3,046 |
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- Definition
Fair value of derivative asset, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Fair value of derivative liability, presented on a gross basis even when the derivative instrument is subject to master netting arrangements and qualifies for net presentation in the statement of financial position. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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