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Significant Concentration - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 Oil And Natural Gas [Member] | Dec. 31, 2011 JIB Receivables [Member] | Dec. 31, 2013 Sales [Member] Musket Corporation [Member] | Dec. 31, 2012 Sales [Member] Musket Corporation [Member] | Dec. 31, 2011 Sales [Member] Texon L.P. [Member] | Dec. 31, 2011 Sales [Member] Plains All American Pipeline L.P. [Member] | Dec. 31, 2011 Sales [Member] Enserco Energy Inc. [Member] | Dec. 31, 2013 Accounts Receivable [Member] Statoil Oil & Gas LP [Member] | Dec. 31, 2013 Accounts Receivable [Member] Continental Resources Inc [Member]
Significant Concentrations [Line Items] |  |  |  |  |  |  |  |  |  |
Concentration risk |  |  |  | 11.00% | 10.00% | 18.00% | 16.00% | 15.00% | 15.00% | 10.00%
Purchasers accounted for more than 10% of the Company's total sales | No other | No other | No other |  |  |  |  |  |  |

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13537-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13531-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592 + Details
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- Definition Disclosure of the extent of enterprise reliance on its major customers. For example, includes revenues from transactions with a single external customer amounting to 10 percent or more of the entity's revenues, the total amount of revenues from each such customer, and the identity of the segment or segments reporting the revenues. A group of entities that the entity knows to be under common control generally will be considered a single customer for inclusion in this item. The federal government, a state government, a local government (for example, a county or municipality), or a foreign government each will generally be considered as a single customer for inclusion in this item. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 42 -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9054-108599 + Details
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