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Changes in Fair Value of Commodity Derivative Contracts Recognized in Earnings (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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| Derivative (gain) loss: | |||
| Realized gain (loss) on commodity contracts | $ 7,665 | $ 9,873 | $ (5,539) |
| Unrealized gain (loss) on commodity contracts | 6,289 | (11,769) | 9,511 |
| Total | $ 13,954 | $ (1,896) | $ 4,256 |
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- Definition
Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open agreements to purchase or sell mineral resources, energy, and agricultural products at some future point held at each balance sheet date, that was included in earnings for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The realized gain or loss related to commodity contracts that have closed. No definition available.
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