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Derivatives (Details) (USD $)
In Thousands, unless otherwise specified |
Jun. 30, 2012
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Dec. 31, 2011
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Jun. 30, 2011
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|---|---|---|---|
| Estimated fair value of Company's commodity derivative instruments for cash collateral and associated cash as collateral | |||
| Net derivative asset position, Collateral paid | $ 151,939 | $ 66,870 | $ 43,191 |
| Net derivative asset position, Fair value of derivatives | (106,629) | (20,480) | 40,476 |
| Net derivative asset position, net | 45,310 | 46,390 | 83,667 |
| Net derivative liability position, Collateral paid | 0 | 0 | 0 |
| Net derivative liability position, Fair value of derivatives | 0 | 0 | 0 |
| Net derivative liability position, net | $ 0 | $ 0 | $ 0 |
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- Details
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- Definition
Net derivative liability position, collateral paid. No definition available.
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- Definition
Fair value of the gross assets less the gross liabilities of a derivative asset or group of derivative assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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- Definition
Fair value of the gross liabilities less the gross assets of a derivative liability or group of derivative liabilities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The amount of cash or securities placed with a broker or counterparty as security for a trading or derivatives securities position which was partially obtained with funds provided by the broker dealer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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