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Commitments and Contingencies (Commitments) (Details) (USD $) | 0 Months Ended |  |  |  | 0 Months Ended |  |  |  |  |  |  |
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Nov. 02, 2012 | Mar. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Mar. 11, 1997 WCBB [Member] wells | Mar. 31, 2013 WCBB [Member] wells | Dec. 31, 2012 WCBB [Member] wells | Mar. 31, 2013 Executive Officer [Member] | Dec. 31, 2012 Executive Officer [Member] | Mar. 31, 2013 Grizzly [Member] | Dec. 31, 2012 Grizzly [Member] | Oct. 05, 2012 Grizzly [Member]
Commitments [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Percentage of interest in WCBB |  |  |  |  | 50.00% |  |  |  |  |  |  |
Contribution to plugging and abandonment trust |  |  |  |  | $ 18,000 |  |  |  |  |  |  |
Annual minimum wells to be plugged |  |  |  |  | 20 |  |  |  |  |  |  |
Tenure of minimum wells to be plugged, years |  |  |  |  | 20 years |  |  |  |  |  |  |
Plugging and abandonment escrow account on the WCBB properties (Note 17) |  | 3,113,000 | 3,113,000 | 3,121,000 |  |  |  |  |  |  |  |
Number of wells plugged |  |  |  |  |  | 354 | 354 |  |  |  |  |
Employement agreement | 3 years |  |  |  |  |  |  |  |  |  |  |
Extension period | 1 year |  |  |  |  |  |  |  |  |  |  |
Notice period | 90 days |  |  |  |  |  |  |  |  |  |  |
Other Commitment |  |  |  |  |  |  |  | 7,600,000 | 7,050,000 |  |  |
Contractual obligation for future salaries and benefits |  |  |  |  |  |  |  |  |  | $ 12,400,000 | $ 6,300,000 | $ 8,500,000

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- Definition Employment Agreement, Notice Period Allowed For Termination + References No definition available. + Details
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- Definition Number Of Wells Plugged + References No definition available. + Details
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- Definition Plugging And Abandonment Escrow Account + References No definition available. + Details
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- Definition Purchasing remaining percent interest in oil and gas property. + References No definition available. + Details
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