Property, Plant and Equipment PROPERTY PLANT AND EQUIPMENT (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Proved Oil and Gas Property, Successful Effort Method	$ 1,768,007	$ 1,670,404
Drilling Cost	2,798,394cnx_DrillingCost	1,937,336cnx_DrillingCost
Coal and other plant and equipment	3,726,514cnx_CoalAndOtherPlantAndEquipment	3,681,051cnx_CoalAndOtherPlantAndEquipment
Coal Properties And Surface Lands	1,358,306cnx_CoalPropertiesAndSurfaceLands	1,404,056cnx_CoalPropertiesAndSurfaceLands
Unproved Oil and Gas Property, Successful Effort Method	1,540,835	1,463,406
Gas Gathering Systems Net	1,088,238cnx_GasGatheringSystemsNet	1,058,008cnx_GasGatheringSystemsNet
Airshafts	468,924cnx_Airshafts	397,466cnx_Airshafts
Property Subject to or Available for Operating Lease, Gross	263,946	393,372
Gas wells and related equipment	716,748cnx_GasWellsAndRelatedEquipment	688,548cnx_GasWellsAndRelatedEquipment
Mine development	414,501cnx_MineDevelopment	354,607cnx_MineDevelopment
Prepaid Royalties	386,245us-gaap_PrepaidRoyalties	381,348us-gaap_PrepaidRoyalties
Other gas assets	123,539cnx_OtherGasAssets	126,239cnx_OtherGasAssets
Advances for Gas Exploration, Development and Production Amount	20,580	22,668
Property, Plant and Equipment, Gross	14,674,777us-gaap_PropertyPlantAndEquipmentGross	13,578,509us-gaap_PropertyPlantAndEquipmentGross
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	4,512,305	4,136,247
Total Property, Plant and Equipment-Net	10,162,472us-gaap_PropertyPlantAndEquipmentNet	9,442,262us-gaap_PropertyPlantAndEquipmentNet
Property, Plant and Equipment, Other, Net		$ 9,442,262

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Coal And Other Plant And Equipment

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Coal Properties And Surface Lands

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Gas Gathering Systems, Net

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Gas Wells and Related Equipment

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Mine Development

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Other Gas Assets

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of asset related to consideration paid in advance for royalties that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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The net amount of capitalized assets classified as property, plant and equipment not otherwise defined in the taxonomy.

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

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