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Equity Investments (Grizzly and Diamondback Balance Sheet Disclosures) (Details) (USD $)
In Thousands, unless otherwise specified |
Mar. 31, 2013
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Dec. 31, 2012
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Dec. 31, 2011
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Grizzly Oil Sands ULC [Member]
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| Schedule of Equity Method Investments [Line Items] | |||
| Current assets | $ 30,098 | $ 21,247 | |
| Noncurrent assets | 720,550 | 284,361 | |
| Current liabilities | 42,547 | 25,984 | |
| Noncurrent liabilities | 14,515 | 1,780 | |
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Diamondback Energy LLC [Member]
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| Schedule of Equity Method Investments [Line Items] | |||
| Current assets | 34,516 | 50,275 | 30,812 |
| Noncurrent assets | 613,947 | 556,426 | 232,766 |
| Current liabilities | 76,336 | 79,232 | 42,298 |
| Noncurrent liabilities | $ 104,093 | $ 65,401 | $ 92,243 |
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- Definition
The amount of current assets reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The amount of current liabilities reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The amount of noncurrent assets reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The amount of noncurrent liabilities reported by an equity method investment of the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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