Asset Retirement Obligations  | 
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| Asset Retirement Obligation Disclosure [Text Block] | 
 6. Asset Retirement Obligations  Our ARO represent the estimated present value of the amount incurred to plug, abandon and remediate our properties at the end of their productive lives. A summary of the changes to our ARO is as follows (in thousands):  
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- Definition The 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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- References No definition available. 
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