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Mineral Property Transactions (Details) (USD $) In Millions, unless otherwise specified | 6 Months Ended
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Jun. 30, 2012 acre
Gas and Oil Acreage [Line Items] |
Number of Projects | 7
Percentage of initial working interest (in hundredths) | 26.50%
Percentage of net revenue interest (in hundredths) | 19.60%
Reduced percentage of net revenue interests after payout of initial well cost (in hundredths) | 14.70%
Reduced percentage of working interests after payout of initial well cost (in hundredths) | 19.80%
Gross acres acquired in Woodbine acquisition (in acres) | 6,766
Net acres acquired in Woodbine acquisition (in acres) | 1,274
Purchase price of Woodbine acquisition | $ 1.7
Bakken/Three Forks Shale [Member] |
Gas and Oil Acreage [Line Items] |
Percentage of undeveloped acreage sold (in hundredths) | 75.00%
Proceeds from sale of undeveloped acreage | 16.7
Proceeds from reimbursed well costs | 1.4
Transfer of costs from unevaluated properties to proved properties | 5.3
Percentage of interest in undeveloped acreage retained (in hundredths) | 25.00%
Number of developed wells in which our original working interest is retained | 10
Percentage of average working interest in the remaining locations (in hundredths) | 8.75%
Montana Acreage [Member] |
Gas and Oil Acreage [Line Items] |
Percentage of undeveloped acreage sold (in hundredths) | 87.50%
Transfer of costs from unevaluated properties to proved properties | $ 1.0
Percentage of interest in undeveloped acreage retained (in hundredths) | 12.50%
Minimum percentage of net revenue interest in lease owned (in hundredths) | 81.00%
Percentage of net revenue interest delivered to purchaser (in hundredths) | 80.00%
Percentage of overriding royalty interest delivered to land broker (in hundredths) | 1.00%
Percentage of commission paid to land broker (in hundredths) | 10.00%
Minimum [Member] | Bakken/Three Forks Shale [Member] |
Gas and Oil Acreage [Line Items] |
Expected net revenue interests in new wells after sale (in hundredths) | 6.7375%
Maximum [Member] | Bakken/Three Forks Shale [Member] |
Gas and Oil Acreage [Line Items] |
Expected net revenue interests in new wells after sale (in hundredths) | 7.00%
GeoResources, Inc [Member] | Bakken/Three Forks Shale [Member] |
Gas and Oil Acreage [Line Items] |
Percentage of undeveloped acreage sold (in hundredths) | 56.25%
Yuma Exploration and Production Company, Inc [Member] | Bakken/Three Forks Shale [Member] |
Gas and Oil Acreage [Line Items] |
Percentage of undeveloped acreage sold (in hundredths) | 18.75%

X
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- Definition Represents the expected net revenue interests in new wells after sale. + References No definition available. + Details
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- Definition Represent the minimum percentage of net revenue interest in lease owned as per the agreement. + References No definition available. + Details
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- Definition Represents the percentage of acreage sold. + References No definition available. + Details
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- Definition Represents the reduced percentage of net revenue interests after payout of initial well cost. + References No definition available. + Details
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- Definition The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141 -Paragraph 51 -Subparagraph d -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
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- Details
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- Definition Area spaced or assigned to productive wells in which a working interest is owned. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 2 -Paragraph 4 -Subparagraph A + Details
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- Definition Fractional interest owned based on working interests or other economic arrangements of area spaced or assigned to productive wells. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 2 -Paragraph 4 -Subparagraph A + Details
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- Definition The total number of producing oil wells and oil wells capable of production, in which the entity owns an undivided working interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 2 -Paragraph 4 -Subparagraph A + Details
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