Supplemental Gas Data Acreages (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014 acre	Dec. 31, 2013
Gas and Oil Acreage [Line Items]
Unproved Oil and Gas Property, Successful Effort Method	$ 1,540,835	$ 1,463,406
Proved Oil and Gas Property, Successful Effort Method	$ 1,768,007	$ 1,670,404
Productive Gas Wells, Number of Wells, Gross	17,044,000
Gas and Oil Acreage, Undeveloped, Net	63,801,000us-gaap_GasAndOilAreaUndevelopedNet
unproved acreage gross	4,946,174,000cnx_UnprovedAcreageGross
Gas and Oil Acreage, Unproved, Net	3,933,975,000cnx_GasAndOilAcreageUnprovedNet
Total Acreage - Gross	5,596,726,000cnx_TotalAcreageGross
Total Acreage - Net	4,513,215,000cnx_TotalAcreageNet
Productive Gas Wells, Number of Wells, Net	12,918,000
Productive Oil Wells, Number of Wells, Gross	154,000	34,000
Gas and Oil Area, Developed, Gross	537,935,000us-gaap_GasAndOilAreaDevelopedGross
Gas and Oil Area, Developed, Net	515,439,000us-gaap_GasAndOilAreaDevelopedNet
Gas and Oil Area, Undeveloped, Gross	112,617,000us-gaap_GasAndOilAreaUndevelopedGross

Gas and Oil Acreage, Unproved, Net

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Total acreage

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Total Acreage - Net

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unproved acreage gross

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Area spaced or assigned to productive wells in which a working interest is owned.

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Fractional interest owned based on working interests or other economic arrangements of area spaced or assigned to productive wells.

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Lease area in which a working interest is owned and on which wells have not been drilled or completed to a point that would permit the production of commercial quantities of oil and gas regardless of whether or not such area contains proved reserves.

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Fractional interest owned based on working interests or other economic arrangements of lease area on which wells have not been drilled or completed to a point that would permit the production of commercial quantities of oil and gas regardless of whether or not such area contains proved reserves.

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The total number of producing gas wells and gas wells capable of production, in which the entity owns an undivided working interest.

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The total number of producing gas wells and gas wells capable of production, in which the entity owns a fractional working interest.

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The total number of producing oil wells and oil wells capable of production, in which the entity owns an undivided working interest.

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Oil and Gas properties with proved reserves under the successful effort method.

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Oil and Gas properties with unproved reserves under the successful effort method.

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