| **DERIVATIVE FINANCIAL INSTRUMENTS**                                  | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 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| **DERIVATIVE FINANCIAL INSTRUMENTS [Abstract]**                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         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| Derivative Instruments and Hedging Activities Disclosure [Text Block] | DERIVATIVE FINANCIAL INSTRUMENTSAs of March 31, 2012, we had derivative instruments in place for a portion of our anticipated production through 2015 for a total of 72,997 BBtu of natural gas and 3,134 MBbls of crude oil.        The following table presents the location and fair value amounts of our derivative instruments on the balance sheets. These derivative instruments were comprised of commodity floors, collars and swaps, basis protection swaps and physical sales and purchases.      Fair ValueDerivatives instruments not designated as hedges (1): Balance sheet line item March 31,2012 December 31,2011     (in thousands)Derivative assets:Current       Commodity contracts       Related to natural gas and crude oil sales Fair value of derivatives $64,099 $51,220 Related to affiliated partnerships (2) Fair value of derivatives 8,959 8,018 Related to natural gas marketing Fair value of derivatives 1,691 1,528 Basis protection contracts       Related to natural gas marketing Fair value of derivatives 29 43     74,778 60,809 Non Current       Commodity contracts       Related to natural gas and crude oil sales Fair value of derivatives 31,514 34,938 Related to affiliated partnerships (2) Fair value of derivatives 5,207 6,134 Related to natural gas marketing Fair value of derivatives 11 103 Basis protection contracts       Related to natural gas marketing Fair value of derivatives 19 —     36,751 41,175Total derivative assets    $111,529 $101,984        Derivative liabilities:Current       Commodity contracts       Related to natural gas and crude oil sales Fair value of derivatives $10,492 $7,498 Related to affiliated partnerships (3) Fair value of derivatives 276 211 Related to natural gas marketing Fair value of derivatives 1,585 1,384 Basis protection contracts       Related to natural gas and crude oil sales Fair value of derivatives 15,166 15,762 Related to affiliated partnerships (3) Fair value of derivatives 2,992 3,116 Related to natural gas marketing Fair value of derivatives 2 3     30,513 27,974 Non Current       Commodity contracts       Related to natural gas and crude oil sales Fair value of derivatives 13,378 4,357 Related to affiliated partnerships (3) Fair value of derivatives 123 113 Related to natural gas marketing Fair value of derivatives 7 93 Basis protection contracts       Related to natural gas and crude oil sales Fair value of derivatives 10,281 13,820 Related to affiliated partnerships (3) Fair value of derivatives 2,024 2,723 Related to natural gas marketing Fair value of derivatives 2 —     25,815 21,106Total derivative liabilities    $56,328 $49,080        __________(1)As of March 31, 2012, and December 31, 2011, none of our derivative instruments were designated as hedges. (2) Represents derivative positions designated to our affiliated partnerships; accordingly, our accompanying balance sheets include a corresponding payable to our affiliated partnerships representing their proportionate share of the derivative assets. (3) Represents derivative positions designated to our affiliated partnerships; accordingly, our accompanying balance sheets include a corresponding receivable from our affiliated partnerships representing their proportionate share of the derivative liabilities.        The following table presents the impact of our derivative instruments on our statements of operations.  Three Months Ended March 31,  2012 2011Statement of operations line item Reclassificationof RealizedGains (Losses)Included in Prior PeriodsUnrealized Realized and UnrealizedGains(Losses) FortheCurrentPeriod Total Reclassificationof RealizedGains (Losses)Included in Prior PeriodsUnrealized Realized and UnrealizedGains(Losses) FortheCurrentPeriod Total  (in thousands)Commodity price risk management gain, net            Realized gains $8,628 $1,299 $9,927 $3,322 $466 $3,788Unrealized gains (losses) (8,628) 10,202 1,574 (3,322) (24,348) (27,670)Total commodity price risk management gain (loss), net $— $11,501 $11,501 $— $(23,882) $(23,882)Sales from natural gas marketing            Realized gains $684 $109 $793 $1,007 $135 $1,142Unrealized gains (losses) (684) 759 75 (1,007) (10) (1,017)Total sales from natural gas marketing $— $868 $868 $— $125 $125Cost of natural gas marketing            Realized losses $(591) $(154) $(745) $(770) $(190) $(960)Unrealized gains (losses) 591 (707) (116) 770 172 942Total cost of natural gas marketing $— $(861) $(861) $— $(18) $(18)             Derivative Counterparties. A significant portion of our liquidity is concentrated in derivative instruments that enable us to manage a portion of our exposure to price volatility from producing natural gas and crude oil. These arrangements expose us to credit risk of nonperformance by our counterparties. We primarily use financial institutions, who are also major lenders in our credit facility agreement, as counterparties to our derivative contracts. To date, we have had no counterparty default losses. We have evaluated the credit risk of our derivative assets from our counterparties using relevant credit market default rates, giving consideration to amounts outstanding for each counterparty and the duration of each outstanding derivative position. Based on our evaluation, the impact of the nonperformance of our counterparties on the fair value of our derivative instruments is not significant. The following table presents the counterparties that expose us to credit risk as of March 31, 2012, with regard to our derivative assets. Counterparty Name Fair Value ofDerivative AssetsAs of March 31, 2012  (in thousands)   JPMorgan Chase Bank, N.A. (1) $55,769Crèdit Agricole CIB (1) 19,441Wells Fargo Bank, N.A. (1) 20,099Other lenders in our credit facility 16,135Various (2) 85Total $111,529   __________(1)Major lender in our credit facility, see Note 7.(2)Represents a total of 10 counterparties. |

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| - Definition
The entire disclosure for the entity's entire derivative instruments and hedging activities.  Describes an entity's risk management strategies, derivatives in hedging activities and non-hedging derivative instruments, the assets, obligations, liabilities, revenues and expenses arising therefrom, and the amounts of and methodologies and assumptions used in determining the amounts of such items.
+ References
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