Guarantor Subsidiaries, Condensed Statement of Cash Flows (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by (Used in) Investing Activities, Continuing Operations	$ (979,126,000)	$ (671,621,000)	$ (375,214,000)
Cash Provided by (Used in) Investing Activities, Discontinued Operations	777,145,000	(328,789,000)	(203,310,000)
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	553,570,000	457,342,000	1,328,871,000
Cash Provided by (Used in) Operating Activities, Discontinued Operations	105,206,000	270,771,000	198,735,000
Net Cash Provided by Operating Activities	658,776,000	728,113,000	1,527,606,000
Investing Activities:
Capital Expenditures	(1,496,056,000)	(1,245,497,000)	(1,178,375,000)
Increase (Decrease) in Restricted Cash	68,673,000	(48,294,000)	0
Net Investment in Equity Affiliates	(35,712,000)	(23,451,000)	55,876,000
Proceeds from Sales of Assets	483,969,000	645,621,000	747,285,000
Net Cash Used in Investing Activities	(201,981,000)	(1,000,410,000)	(578,524,000)
Financing Activities:
Dividends Paid	(85,832,000)	(142,278,000)	(96,356,000)
(Payments on) Proceeds from Short-Term Borrowings	0	0	(284,000,000)
Repayments of Other Debt	(31,544,000)	16,195,000	(11,080,000)
Payments on Securitization Facility	37,846,000		(200,000,000)
Payments On Long Term Notes Including Redemption Premium	0	0	(265,785,000)
Proceeds from Issuance of Long-Term Notes	0	0	250,000,000
Proceeds from Issuance of Common Stock	3,727,000	8,278,000	0
Other Financing Activities	778,000	53,024,000	(9,452,000)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations	(150,717,000)	(80,976,000)	(605,593,000)
Cash Provided by (Used in) Financing Activities, Discontinued Operations	(520,000)	(601,000)	(547,000)
Net Cash (Used in) Provided by Financing Activities	(151,237,000)	(81,577,000)	(606,140,000)
Parent Issuer
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by (Used in) Investing Activities, Continuing Operations	259,168,000	150,027,000	(41,162,000)
Cash Provided by (Used in) Investing Activities, Discontinued Operations	0	0	0
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	51,093,000	(58,410,000)	530,444,000
Cash Provided by (Used in) Operating Activities, Discontinued Operations	0	0	0
Net Cash Provided by Operating Activities	51,093,000	(58,410,000)	530,444,000
Investing Activities:
Capital Expenditures	(68,796,000)	(49,973,000)	(41,172,000)
Increase (Decrease) in Restricted Cash	0	0
Net Investment in Equity Affiliates	0	200,000,000	0
Proceeds from Sales of Assets	327,964,000	0	10,000
Net Cash Used in Investing Activities	259,168,000	150,027,000	(41,162,000)
Financing Activities:
Dividends Paid	14,168,000	(142,278,000)	(96,356,000)
(Payments on) Proceeds from Short-Term Borrowings	0		(155,000,000)
Repayments of Other Debt	25,952,000
Payments on Securitization Facility	0		(200,000,000)
Payments On Long Term Notes Including Redemption Premium			(265,785,000)
Proceeds from Issuance of Long-Term Notes			250,000,000
Proceeds from Issuance of Common Stock	3,727,000	8,278,000
Other Financing Activities	778,000	22,532,000	5,749,000
Net Cash Provided by (Used in) Financing Activities, Continuing Operations	(7,279,000)	(111,468,000)	(461,392,000)
Cash Provided by (Used in) Financing Activities, Discontinued Operations	0	0	0
Net Cash (Used in) Provided by Financing Activities	(7,279,000)	(111,468,000)	(461,392,000)
Cnx Gas Guarantor [Member]
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by (Used in) Investing Activities, Continuing Operations	(665,132,000)	(209,907,000)	132,970,000
Cash Provided by (Used in) Investing Activities, Discontinued Operations	0	0	0
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	440,763,000	82,036,000	329,360,000
Cash Provided by (Used in) Operating Activities, Discontinued Operations	0	0	0
Net Cash Provided by Operating Activities	440,763,000	82,036,000	329,360,000
Investing Activities:
Capital Expenditures	(968,607,000)	(532,636,000)	(664,612,000)
Increase (Decrease) in Restricted Cash	0	0
Net Investment in Equity Affiliates	(47,500,000)	(37,400,000)	50,626,000
Proceeds from Sales of Assets	350,975,000	360,129,000	746,956,000
Net Cash Used in Investing Activities	(665,132,000)	(209,907,000)	132,970,000
Financing Activities:
Dividends Paid	(100,000,000)	(200,000,000)	0
(Payments on) Proceeds from Short-Term Borrowings	332,487,000		(129,000,000)
Repayments of Other Debt	0
Payments on Securitization Facility	0		0
Payments On Long Term Notes Including Redemption Premium			0
Proceeds from Issuance of Long-Term Notes			0
Proceeds from Issuance of Common Stock	0	0
Other Financing Activities	(5,232,000)	(5,504,000)	(13,162,000)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations	227,255,000	(205,504,000)	(142,162,000)
Cash Provided by (Used in) Financing Activities, Discontinued Operations	0	0	0
Net Cash (Used in) Provided by Financing Activities	227,255,000	(205,504,000)	(142,162,000)
Other Subsidiary Guarantors
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by (Used in) Investing Activities, Continuing Operations	(573,274,000)	(411,995,000)	(468,496,000)
Cash Provided by (Used in) Investing Activities, Discontinued Operations	0	0	0
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	572,683,000	412,293,000	465,847,000
Cash Provided by (Used in) Operating Activities, Discontinued Operations	0	0	0
Net Cash Provided by Operating Activities	572,683,000	412,293,000	465,847,000
Investing Activities:
Capital Expenditures	(458,653,000)	(662,888,000)	(472,591,000)
Increase (Decrease) in Restricted Cash	(68,673,000)	48,294,000
Net Investment in Equity Affiliates	11,788,000	13,949,000	5,250,000
Proceeds from Sales of Assets	(195,082,000)	285,238,000	(1,155,000)
Net Cash Used in Investing Activities	(573,274,000)	(411,995,000)	(468,496,000)
Financing Activities:
Dividends Paid	0	0	0
(Payments on) Proceeds from Short-Term Borrowings	0		0
Repayments of Other Debt	4,800,000
Payments on Securitization Facility	0		0
Payments On Long Term Notes Including Redemption Premium			0
Proceeds from Issuance of Long-Term Notes			0
Proceeds from Issuance of Common Stock	0	0
Other Financing Activities	5,232,000	(1,408,000)	(1,246,000)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations	432,000	(1,408,000)	(1,246,000)
Cash Provided by (Used in) Financing Activities, Discontinued Operations	0	0	0
Net Cash (Used in) Provided by Financing Activities	432,000	(1,408,000)	(1,246,000)
Non-Guarantors
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by (Used in) Investing Activities, Continuing Operations	112,000	254,000	1,474,000
Cash Provided by (Used in) Investing Activities, Discontinued Operations	777,145,000	(328,789,000)	(203,310,000)
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	(843,456,000)	21,423,000	3,220,000
Cash Provided by (Used in) Operating Activities, Discontinued Operations	105,206,000	270,771,000	198,735,000
Net Cash Provided by Operating Activities	(738,250,000)	292,194,000	201,955,000
Investing Activities:
Capital Expenditures	0	0	0
Increase (Decrease) in Restricted Cash	0	0
Net Investment in Equity Affiliates	0	0	0
Proceeds from Sales of Assets	112,000	254,000	1,474,000
Net Cash Used in Investing Activities	777,257,000	(328,535,000)	(201,836,000)
Financing Activities:
Dividends Paid	0	0	0
(Payments on) Proceeds from Short-Term Borrowings	0		0
Repayments of Other Debt	792,000
Payments on Securitization Facility	37,846,000		0
Payments On Long Term Notes Including Redemption Premium			0
Proceeds from Issuance of Long-Term Notes			0
Proceeds from Issuance of Common Stock	0	0
Other Financing Activities	0	37,404,000	(793,000)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations	(38,638,000)	37,404,000	(793,000)
Cash Provided by (Used in) Financing Activities, Discontinued Operations	(520,000)	(601,000)	(547,000)
Net Cash (Used in) Provided by Financing Activities	(39,158,000)	36,803,000	(1,340,000)
Elimination
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by (Used in) Investing Activities, Continuing Operations	0	(200,000,000)	0
Cash Provided by (Used in) Investing Activities, Discontinued Operations	0	0	0
Net Cash Provided by (Used in) Operating Activities, Continuing Operations	332,487,000	0	0
Cash Provided by (Used in) Operating Activities, Discontinued Operations	0	0	0
Net Cash Provided by Operating Activities	332,487,000	0	0
Investing Activities:
Capital Expenditures	0	0	0
Increase (Decrease) in Restricted Cash	0	0
Net Investment in Equity Affiliates	0	(200,000,000)	0
Proceeds from Sales of Assets	0	0	0
Net Cash Used in Investing Activities	0	(200,000,000)	0
Financing Activities:
Dividends Paid	0	200,000,000	0
(Payments on) Proceeds from Short-Term Borrowings	(332,487,000)		0
Repayments of Other Debt	0
Payments on Securitization Facility	0		0
Payments On Long Term Notes Including Redemption Premium			0
Proceeds from Issuance of Long-Term Notes			0
Proceeds from Issuance of Common Stock	0	0
Other Financing Activities	0	0	0
Net Cash Provided by (Used in) Financing Activities, Continuing Operations	(332,487,000)	200,000,000	0
Cash Provided by (Used in) Financing Activities, Discontinued Operations	0	0	0
Net Cash (Used in) Provided by Financing Activities	$ (332,487,000)	$ 200,000,000	$ 0