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Contingencies (Details) (USD $) |  | 0 Months Ended | 1 Months Ended | 36 Months Ended | 48 Months Ended | 0 Months Ended | 4 Months Ended |  |  | 12 Months Ended | 0 Months Ended
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Dec. 31, 2013 | Apr. 20, 2009 Louisiana Department of Revenue Tax Litigation [Member] | Dec. 31, 2010 Louisiana Department of Revenue Tax Litigation [Member] lawsuit | Dec. 31, 2007 Louisiana Department of Revenue Tax Litigation [Member] | Dec. 31, 2010 Louisiana Department of Revenue Tax Litigation [Member] lawsuit | Dec. 09, 2010 Reed Litigation [Member] defendant plaintiff acre | Jul. 31, 2010 Reed Litigation [Member] defendant | Dec. 07, 2010 Reed Litigation [Member] defendant acre | Dec. 06, 2010 Reed Litigation [Member] acre | Dec. 31, 2013 Maximum [Member] | Dec. 31, 2013 Shell Trading Company [Member] Oil [Member] | Dec. 31, 2012 Shell Trading Company [Member] Oil [Member] | Dec. 31, 2011 Shell Trading Company [Member] Oil [Member] | Dec. 31, 2013 Markwest Utica [Member] Natural Gas Liquids [Member] | Dec. 31, 2013 Sequent [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Dec. 31, 2012 Diamondback [Member] Oil [Member] | Dec. 31, 2011 Diamondback [Member] Oil [Member] | Dec. 31, 2012 Diamondback [Member] Natural Gas Liquids [Member] | Dec. 31, 2011 Diamondback [Member] Natural Gas Liquids [Member] | Dec. 31, 2011 Diamondback [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Dec. 31, 2011 Hilcorp Energy Company [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Dec. 31, 2012 North American Gas [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Dec. 31, 2013 Hess [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Dec. 31, 2012 Hess [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Dec. 31, 2013 Interstate Gas [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Dec. 31, 2012 Chevron [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Dec. 31, 2011 Chevron [Member] Natural Gas, Per Thousand Cubic Feet [Member] | Jul. 31, 2010 Individual Counterparty [Member] Reed Litigation [Member] plaintiff | Jul. 31, 2010 Limited Liability Company [Member] Reed Litigation [Member] plaintiff
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingency, Number of Plaintiffs |  |  |  |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 | 1
Loss Contingency, Number of Defendants |  |  |  |  |  | 6 | 15 | 21 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash, FDIC Insured Amount |  |  |  |  |  |  |  |  |  | $ 250,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alleged Severance Taxes Underpayment |  |  |  | 1,800,000 | 12,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cash, Uninsured Amount | 457,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage Of Production Sold |  |  |  |  |  |  |  |  |  |  | 99.00% | 92.00% | 93.00% | 100.00% | 32.00% | 8.00% | 7.00% | 91.00% | 100.00% | 22.00% | 50.00% | 41.00% | 31.00% | 18.00% | 17.00% | 16.00% | 27.00% |  |
Original Number Of Acreage In Litigation |  |  |  |  |  |  |  |  | 240 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amended Number Of Acreage In Litigation |  |  |  |  |  |  |  | 1,700 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingency, Damages Sought, Value |  | $ 2,300,000 | $ 4,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingency, Pending Claims, Number |  |  | 2 |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Alleged severance tax underpayment by the Louisiana Department of Revenue due to fixed price contracts + References No definition available. + Details
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- Definition Amended number of acreage in litigation + References No definition available. + Details
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- Definition Original number of acreage in litigation + References No definition available. + Details
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- Definition Percentage of production sold to purchaser in the period + References No definition available. + Details
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- Definition The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation. + References No definition available. + Details
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- Definition The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation. + References No definition available. + Details
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- Details
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- Definition The value (monetary amount) of the award the plaintiff seeks in the legal matter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349 + Details
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- Definition Number of defendants named in a legal action. + References No definition available. + Details
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- Definition Number of plaintiffs that have filed claims pertaining to a loss contingency. + References No definition available. + Details
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- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 + Details
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