Guarantor Subsidiaries, Condensed Statement of Cash Flows (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by Operating Activities	$ 268,280	$ 229,486
Investing Activities:
Capital Expenditures	(405,972)	(306,446)
Other Investing Activities	138,636
Net Cash Used in Investing Activities	(231,542)	(288,085)
Proceeds from Sales of Assets	138,636	28,611
Financing Activities:
Dividends Paid	0	(28,387)
(Payments on) Proceeds from Short-Term Borrowings	0
Proceeds from Issuance of Common Stock	909	54
Other Financing Activities	1,770	893
Payments on Securitization Facility	7,727
Repayments of Other Debt	(27,601)	(2,330)
Net Cash (Used in) Provided by Financing Activities	(33,558)	(29,824)
Equity Method Investment, Dividends or Distributions	(12,500)	(10,250)
Increase (Decrease) in Restricted Cash	48,294	0
Parent Issuer
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by Operating Activities	59,082	123,513
Investing Activities:
Capital Expenditures	(1,504)	(13,562)
Other Investing Activities	(75)
Net Cash Used in Investing Activities	(1,579)	(13,562)
Proceeds from Sales of Assets		0
Financing Activities:
Dividends Paid		91,613
(Payments on) Proceeds from Short-Term Borrowings	(29,000)
Other Financing Activities	1,770	893
Payments on Securitization Facility	0
Repayments of Other Debt	(25,612)	(236)
Net Cash (Used in) Provided by Financing Activities	(52,842)	92,270
Equity Method Investment, Dividends or Distributions	0	0
Increase (Decrease) in Restricted Cash	0
CNX Gas Guarantor
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by Operating Activities	190,004	54,417
Investing Activities:
Capital Expenditures	(207,129)	(98,455)
Other Investing Activities	343
Net Cash Used in Investing Activities	(218,786)	(104,095)
Proceeds from Sales of Assets		4,359
Financing Activities:
Dividends Paid		(120,000)
(Payments on) Proceeds from Short-Term Borrowings	29,000
Other Financing Activities	(1,400)	(844)
Payments on Securitization Facility	0
Repayments of Other Debt	0	0
Net Cash (Used in) Provided by Financing Activities	27,600	(120,844)
Equity Method Investment, Dividends or Distributions	(12,000)	(9,999)
Increase (Decrease) in Restricted Cash	0
Other Guarantors Subsidiaries [Member]
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by Operating Activities	11,589	51,118
Investing Activities:
Capital Expenditures	(197,339)	(194,429)
Other Investing Activities	138,365
Net Cash Used in Investing Activities	(11,180)	(170,430)
Proceeds from Sales of Assets		24,250
Financing Activities:
Dividends Paid		0
(Payments on) Proceeds from Short-Term Borrowings	0
Other Financing Activities	1,400	844
Payments on Securitization Facility	0
Repayments of Other Debt	(1,813)	(1,844)
Net Cash (Used in) Provided by Financing Activities	(413)	(1,000)
Equity Method Investment, Dividends or Distributions	(500)	(251)
Increase (Decrease) in Restricted Cash	48,294
Non-Guarantors
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by Operating Activities	7,605	438
Investing Activities:
Capital Expenditures	0	0
Other Investing Activities	3
Net Cash Used in Investing Activities	3	2
Proceeds from Sales of Assets		2
Financing Activities:
Dividends Paid		0
(Payments on) Proceeds from Short-Term Borrowings	0
Other Financing Activities		0
Payments on Securitization Facility	7,727
Repayments of Other Debt	(176)	(250)
Net Cash (Used in) Provided by Financing Activities	(7,903)	(250)
Equity Method Investment, Dividends or Distributions	0	0
Increase (Decrease) in Restricted Cash	0
Consolidation, Eliminations [Member]
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net Cash Provided by Operating Activities	0	0
Investing Activities:
Capital Expenditures	0	0
Other Investing Activities	0
Net Cash Used in Investing Activities	0	0
Proceeds from Sales of Assets		0
Financing Activities:
Dividends Paid		0
(Payments on) Proceeds from Short-Term Borrowings	0
Other Financing Activities	0	0
Payments on Securitization Facility	0
Repayments of Other Debt	0	0
Net Cash (Used in) Provided by Financing Activities	0	0
Equity Method Investment, Dividends or Distributions	0	0
Increase (Decrease) in Restricted Cash	$ 0