Derivative Financial Instruments (Estimated Fair Value of Derivative Contracts) (Detail) (USD $)
In Thousands, unless otherwise specified |
Jun. 30, 2012
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Dec. 31, 2011
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Prepaid and other assets
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Derivatives, Fair Value [Line Items] | ||
Estimated fair value of assets commodity derivative contracts | $ 9,188 | $ 2,341 |
Other assets
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Derivatives, Fair Value [Line Items] | ||
Estimated fair value of assets commodity derivative contracts | 4,022 | 1,746 |
Accrued liabilities
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Derivatives, Fair Value [Line Items] | ||
Estimated fair value of liabilities commodity derivative contracts | $ 7,199 |
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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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