CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
OPERATING REVENUES
Natural gas	$ 360,191us-gaap_NaturalGasProductionRevenue	$ 432,809us-gaap_NaturalGasProductionRevenue
Crude oil and condensate	62,558us-gaap_OilAndCondensateRevenue	59,144us-gaap_OilAndCondensateRevenue
Gain (loss) on derivative instruments	34,123us-gaap_GainLossOnSaleOfDerivatives	0us-gaap_GainLossOnSaleOfDerivatives
Brokered natural gas	4,827cog_BrokeredNaturalGasRevenue	13,153cog_BrokeredNaturalGasRevenue
Other	3,066us-gaap_OtherSalesRevenueNet	4,697us-gaap_OtherSalesRevenueNet
TOTAL OPERATING REVENUES	464,765us-gaap_Revenues	509,803us-gaap_Revenues
OPERATING EXPENSES
Direct operations	36,017us-gaap_DirectOperatingCosts	35,834us-gaap_DirectOperatingCosts
Transportation and gathering	121,235	77,765
Brokered natural gas	3,739cog_BrokeredNaturalGasCosts	11,860cog_BrokeredNaturalGasCosts
Taxes other than income	11,280	13,044
Exploration	8,732us-gaap_ExplorationExpense	6,474us-gaap_ExplorationExpense
Depreciation, depletion and amortization	175,497	147,418
General and administrative	22,529us-gaap_GeneralAndAdministrativeExpense	21,636us-gaap_GeneralAndAdministrativeExpense
TOTAL OPERATING EXPENSES	379,029us-gaap_OperatingExpenses	314,031us-gaap_OperatingExpenses
Earnings (loss) on equity method investments	1,421	0
Gain (loss) on sale of assets	138	(1,285)
INCOME FROM OPERATIONS	87,295us-gaap_OperatingIncomeLoss	194,487us-gaap_OperatingIncomeLoss
Interest expense	23,566us-gaap_InterestIncomeExpenseNet	16,557us-gaap_InterestIncomeExpenseNet
Income before income taxes	63,729	177,930
Income tax expense	23,474us-gaap_IncomeTaxExpenseBenefit	70,899us-gaap_IncomeTaxExpenseBenefit
NET INCOME	$ 40,255	$ 107,031
Earnings per share
Basic (in dollars per share)	$ 0.10us-gaap_EarningsPerShareBasic	$ 0.26us-gaap_EarningsPerShareBasic
Diluted (in dollars per share)	$ 0.10us-gaap_EarningsPerShareDiluted	$ 0.26us-gaap_EarningsPerShareDiluted
Weighted-average common shares outstanding
Basic (in shares)	413,344	416,900
Diluted (in shares)	414,771	418,513
Dividends per common share (in dollars per share)	$ 0.02	$ 0.02

Costs incurred in brokering natural gas during the reporting period. The entity buys and sells natural gas utilizing separate purchase and sale transactions, typically with separate counterparties, whereby the entity and/or counterparty takes title to the natural gas purchases or sold. The entity recognizes the related revenues and expenses gross and realizes brokered margin as a result of buying and selling natural gas.

No definition available.