Guarantor Subsidiaries Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013	Dec. 31, 2012
Schedule of Condensed Consolidating Balance Sheets [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	$ 352,187	$ 291,675
Current Assets:
Cash and Cash Equivalents	147,393	327,420	71,918	21,862
Accounts and Notes Receivable:
Trade	275,431	332,574
Notes Receivable, Related Parties, Current	1,328	25,861
Other Receivables	390,484	243,973
Inventories	148,005	157,914
Recoverable Income Taxes	47,060	10,705
Deferred Income Taxes	137,716	211,303
Prepaid Expenses	78,438	135,842
Total Current Assets	1,225,855	1,445,592
Property, Plant and Equipment:
Property, Plant and Equipment	14,160,967	13,578,509
Less-Accumulated Depreciation, Depletion and Amortization	4,384,209	4,136,247
Total Property, Plant and Equipment-Net	9,776,758	9,442,262
Other Assets:
Notes, Loans and Financing Receivable, Net		125
Other	211,847	214,013
Total Other Assets	564,034	505,813
Total Assets	11,566,647	11,393,667	12,752,928
Current Liabilities:
Accounts Payable	504,009	514,580
Accounts Payable (Recoverable)- Related Parties	0	0
Short-Term Notes Payable		0
Current Portion Long-Term Debt	12,127	11,455
Short-Term Notes Payable	0
Other Accrued Liabilities	554,476	565,697
Liabilities of Disposal Group, Including Discontinued Operation, Current	13,054	28,239
Total Current Liabilities	1,083,666	1,119,971
Long-Term Debt:	3,259,381	3,163,559
Deferred Credits and Other Liabilities
Deferred Tax Liabilities, Net		242,643
Deferred Tax Liabilities, Net, Noncurrent	291,928	242,643
Postretirement Benefits Other Than Pensions	959,034	961,127
Pneumoconiosis	111,519	111,971
Mine Closing	320,902	320,723
Gas Well Closing	180,097	175,603
Workers' Compensation	73,406	71,468
Salary Retirement	58,962	48,252
Reclamation	35,779	40,706
Other	132,315	131,355
Total Deferred Credits and Other Liabilities	2,163,942	2,103,848
Total CONSOL Energy Inc. Stockholders' Equity	5,059,658	5,006,289
TOTAL LIABILITIES AND EQUITY	11,566,647	11,393,667
Parent Issuer [Member]
Schedule of Condensed Consolidating Balance Sheets [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	12,078,724	11,965,054
Current Assets:
Cash and Cash Equivalents	134,563	320,473
Accounts and Notes Receivable:
Trade	0	0
Notes Receivable, Related Parties, Current	1,328	1,238
Other Receivables	43,968	17,657
Inventories	0	0
Recoverable Income Taxes	40,402	(16,262)
Deferred Income Taxes	127,367	219,566
Prepaid Expenses	27,524	43,698
Total Current Assets	375,152	586,370
Property, Plant and Equipment:
Property, Plant and Equipment	166,798	173,719
Less-Accumulated Depreciation, Depletion and Amortization	118,911	122,022
Total Property, Plant and Equipment-Net	47,887	51,697
Other Assets:
Notes, Loans and Financing Receivable, Net		125
Other	146,874	145,401
Total Other Assets	12,225,598	12,110,580
Total Assets	12,648,637	12,748,647
Current Liabilities:
Accounts Payable	49,144	91,553
Accounts Payable (Recoverable)- Related Parties	4,406,801	4,629,131
Short-Term Notes Payable		0
Current Portion Long-Term Debt	1,524	1,029
Short-Term Notes Payable	0
Other Accrued Liabilities	103,400	144,612
Liabilities of Disposal Group, Including Discontinued Operation, Current	0	0
Total Current Liabilities	4,560,869	4,866,325
Long-Term Debt:	3,104,101	3,005,458
Deferred Credits and Other Liabilities
Deferred Tax Liabilities, Net		(232,904)
Deferred Tax Liabilities, Net, Noncurrent	(198,720)
Postretirement Benefits Other Than Pensions	0	0
Pneumoconiosis	0	0
Mine Closing	0	0
Gas Well Closing	0	0
Workers' Compensation	0	0
Salary Retirement	58,962	48,252
Reclamation	0	0
Other	63,767	55,227
Total Deferred Credits and Other Liabilities	(75,991)	(129,425)
Total CONSOL Energy Inc. Stockholders' Equity	5,059,658	5,006,289
TOTAL LIABILITIES AND EQUITY	12,648,637	12,748,647
CNX Gas Guarantor [Member]
Schedule of Condensed Consolidating Balance Sheets [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	259,870	206,060
Current Assets:
Cash and Cash Equivalents	11,984	6,238
Accounts and Notes Receivable:
Trade	74,285	71,911
Notes Receivable, Related Parties, Current	0	0
Other Receivables	300,672	207,128
Inventories	15,076	15,185
Recoverable Income Taxes	6,658	26,967
Deferred Income Taxes	10,349	(8,263)
Prepaid Expenses	31,406	65,701
Total Current Assets	450,430	384,867
Property, Plant and Equipment:
Property, Plant and Equipment	7,417,046	6,919,972
Less-Accumulated Depreciation, Depletion and Amortization	1,329,866	1,188,464
Total Property, Plant and Equipment-Net	6,087,180	5,731,508
Other Assets:
Notes, Loans and Financing Receivable, Net		0
Other	16,685	30,728
Total Other Assets	276,555	236,788
Total Assets	6,814,165	6,353,163
Current Liabilities:
Accounts Payable	359,479	324,226
Accounts Payable (Recoverable)- Related Parties	114,744	23,287
Short-Term Notes Payable		332,487
Current Portion Long-Term Debt	6,546	6,258
Short-Term Notes Payable	595,100
Other Accrued Liabilities	120,000	89,080
Liabilities of Disposal Group, Including Discontinued Operation, Current	0	0
Total Current Liabilities	1,195,869	775,338
Long-Term Debt:	40,331	42,852
Deferred Credits and Other Liabilities
Deferred Tax Liabilities, Net		475,547
Deferred Tax Liabilities, Net, Noncurrent	490,648
Postretirement Benefits Other Than Pensions	0	0
Pneumoconiosis	0	0
Mine Closing	0	0
Gas Well Closing	120,508	119,429
Workers' Compensation	0	0
Salary Retirement	0	0
Reclamation	0	0
Other	61,550	61,190
Total Deferred Credits and Other Liabilities	672,706	656,166
Total CONSOL Energy Inc. Stockholders' Equity	4,905,259	4,878,807
TOTAL LIABILITIES AND EQUITY	6,814,165	6,353,163
Other Guarantors Subsidiaries [Member]
Schedule of Condensed Consolidating Balance Sheets [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	123,405	70,222
Current Assets:
Cash and Cash Equivalents	0	0
Accounts and Notes Receivable:
Trade	0	0
Notes Receivable, Related Parties, Current	0	24,623
Other Receivables	41,831	14,969
Inventories	93,925	99,320
Recoverable Income Taxes	0	0
Deferred Income Taxes	0	0
Prepaid Expenses	17,641	24,915
Total Current Assets	153,397	163,827
Property, Plant and Equipment:
Property, Plant and Equipment	6,550,916	6,459,014
Less-Accumulated Depreciation, Depletion and Amortization	2,915,856	2,806,775
Total Property, Plant and Equipment-Net	3,635,060	3,652,239
Other Assets:
Notes, Loans and Financing Receivable, Net		0
Other	39,512	28,831
Total Other Assets	162,917	99,053
Total Assets	3,951,374	3,915,119
Current Liabilities:
Accounts Payable	83,650	89,201
Accounts Payable (Recoverable)- Related Parties	(5,188,815)	(5,121,727)
Short-Term Notes Payable		0
Current Portion Long-Term Debt	3,331	3,372
Short-Term Notes Payable	0
Other Accrued Liabilities	322,966	322,606
Liabilities of Disposal Group, Including Discontinued Operation, Current	0	0
Total Current Liabilities	(4,778,868)	(4,706,548)
Long-Term Debt:	113,082	113,474
Deferred Credits and Other Liabilities
Deferred Tax Liabilities, Net		0
Deferred Tax Liabilities, Net, Noncurrent	0
Postretirement Benefits Other Than Pensions	959,034	961,127
Pneumoconiosis	111,519	111,971
Mine Closing	320,902	320,723
Gas Well Closing	59,589	56,174
Workers' Compensation	73,065	71,136
Salary Retirement	0	0
Reclamation	35,779	40,706
Other	6,998	14,938
Total Deferred Credits and Other Liabilities	1,566,886	1,576,775
Total CONSOL Energy Inc. Stockholders' Equity	7,050,274	6,931,418
TOTAL LIABILITIES AND EQUITY	3,951,374	3,915,119
Non-Guarantors [Member]
Schedule of Condensed Consolidating Balance Sheets [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0	0
Current Assets:
Cash and Cash Equivalents	846	709
Accounts and Notes Receivable:
Trade	201,146	260,663
Notes Receivable, Related Parties, Current	0	0
Other Receivables	4,013	4,219
Inventories	39,004	43,409
Recoverable Income Taxes	0	0
Deferred Income Taxes	0	0
Prepaid Expenses	1,867	1,528
Total Current Assets	246,876	310,528
Property, Plant and Equipment:
Property, Plant and Equipment	26,207	25,804
Less-Accumulated Depreciation, Depletion and Amortization	19,576	18,986
Total Property, Plant and Equipment-Net	6,631	6,818
Other Assets:
Notes, Loans and Financing Receivable, Net		0
Other	8,776	9,053
Total Other Assets	8,776	9,053
Total Assets	262,283	326,399
Current Liabilities:
Accounts Payable	11,736	9,600
Accounts Payable (Recoverable)- Related Parties	72,170	136,822
Short-Term Notes Payable		0
Current Portion Long-Term Debt	726	796
Short-Term Notes Payable	0
Other Accrued Liabilities	8,110	9,399
Liabilities of Disposal Group, Including Discontinued Operation, Current	13,054	28,239
Total Current Liabilities	105,796	184,856
Long-Term Debt:	1,867	1,775
Deferred Credits and Other Liabilities
Deferred Tax Liabilities, Net		0
Deferred Tax Liabilities, Net, Noncurrent	0
Postretirement Benefits Other Than Pensions	0	0
Pneumoconiosis	0	0
Mine Closing	0	0
Gas Well Closing	0	0
Workers' Compensation	341	332
Salary Retirement	0	0
Reclamation	0	0
Other	0	0
Total Deferred Credits and Other Liabilities	341	332
Total CONSOL Energy Inc. Stockholders' Equity	154,279	139,436
TOTAL LIABILITIES AND EQUITY	262,283	326,399
Consolidation, Eliminations [Member]
Schedule of Condensed Consolidating Balance Sheets [Line Items]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	(12,109,812)	(11,949,661)
Current Assets:
Cash and Cash Equivalents	0	0
Accounts and Notes Receivable:
Trade	0	0
Notes Receivable, Related Parties, Current	0	0
Other Receivables	0	0
Inventories	0	0
Recoverable Income Taxes	0	0
Deferred Income Taxes	0	0
Prepaid Expenses	0	0
Total Current Assets	0	0
Property, Plant and Equipment:
Property, Plant and Equipment	0	0
Less-Accumulated Depreciation, Depletion and Amortization	0	0
Total Property, Plant and Equipment-Net	0	0
Other Assets:
Notes, Loans and Financing Receivable, Net		0
Other	0	0
Total Other Assets	(12,109,812)	(11,949,661)
Total Assets	(12,109,812)	(11,949,661)
Current Liabilities:
Accounts Payable	0	0
Accounts Payable (Recoverable)- Related Parties	595,100	332,487
Short-Term Notes Payable		(332,487)
Current Portion Long-Term Debt	0	0
Short-Term Notes Payable	(595,100)
Other Accrued Liabilities	0	0
Liabilities of Disposal Group, Including Discontinued Operation, Current	0	0
Total Current Liabilities	0	0
Long-Term Debt:	0	0
Deferred Credits and Other Liabilities
Deferred Tax Liabilities, Net		0
Deferred Tax Liabilities, Net, Noncurrent	0
Postretirement Benefits Other Than Pensions	0	0
Pneumoconiosis	0	0
Mine Closing	0	0
Gas Well Closing	0	0
Workers' Compensation	0	0
Salary Retirement	0	0
Reclamation	0	0
Other	0	0
Total Deferred Credits and Other Liabilities	0	0
Total CONSOL Energy Inc. Stockholders' Equity	(12,109,812)	(11,949,661)
TOTAL LIABILITIES AND EQUITY	$ (12,109,812)	$ (11,949,661)