|**Asset Retirement Obligations**                                               | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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|**Asset Retirement Obligation [Abstract]**                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Asset Retirement Obligation Disclosure [Text Block]                            | ASSET RETIREMENT OBLIGATIONSThe following table presents the changes in carrying amounts of the asset retirement obligations associated with our working interest in natural gas and crude oil properties:Amount(in thousands)Balance at December 31, 2011$46,566Obligations incurred with development activities and assumed with acquisitions14,066Accretion expense2,839Obligations discharged with disposal of properties and asset retirements(2,196)Balance at September 30, 201261,275Less current portion(1,000)Long-term portion$60,275
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|                                                                               | Amount                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|                                                                               | (in thousands)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
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|Balance at December 31, 2011                                                   | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Obligations incurred with development activities and assumed with acquisitions | 14,066                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|Accretion expense                                                              | 2,839                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
|Obligations discharged with disposal of properties and asset retirements       | (2,196                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|Balance at September 30, 2012                                                  | 61,275                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|Less current portion                                                           | (1,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
|Long-term portion                                                              | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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                    duration X- DefinitionThe entire disclosure for an asset retirement obligation and the associated long-lived asset. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.+ ReferencesReference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7569-110849Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 143 -Paragraph 22 -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**Name:**
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