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Subsequent Events (Details) (USD $) In Millions, except Per Share data, unless otherwise specified | Jan. 18, 2012 | Dec. 31, 2011 Oklahoma Oil And Gas [Member] acre | Feb. 02, 2012 Colt LLC [Member] T
--- | --- | --- | ---
Business Acquisition [Line Items] |  |  |
Area of oil and gas reserve acquired |  | 6,000 |
Amount paid |  | $ 20.0 | $ 40.0
Acquisition of coal reserves |  |  | 26,000,000
Subsequent Events (Textual) [Abstract] |  |  |
Distributions per unit declared | $ 0.55 |  |

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- Definition Area of oil and gas reserve acquired. + References No definition available. + Details
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- Definition Coal reserve acquired. + References No definition available. + Details
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- Definition Partners Capital Account Distributions Per Unit Declared. + References No definition available. + Details
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- Details
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- Definition The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141 -Paragraph 51 -Subparagraph d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Details
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