| **DERIVATIVE FINANCIAL INSTRUMENTS**                                    | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              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| **Derivative Instruments and Hedging Activities Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              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| Derivative Instruments and Hedging Activities Disclosure [Text Block]   | DERIVATIVE FINANCIAL INSTRUMENTSOur results of operations and operating cash flows are affected by changes in market prices for crude oil, natural gas and NGLs. To manage a portion of our exposure to price volatility from producing crude oil and natural gas, we utilize the following economic hedging strategies for each of our business segments.•For crude oil and natural gas sales, we enter into derivative contracts to protect against price declines in future periods. While we structure these derivatives to reduce our exposure to changes in price associated with the derivative commodity, they also limit the benefit we might otherwise have received from price increases in the physical market; and •For natural gas marketing, we enter into fixed-price physical purchase and sale agreements that qualify as derivative contracts. In order to offset the fixed-price physical derivatives in our natural gas marketing, we enter into financial derivative instruments that have the effect of locking in the prices we will receive or pay for the same volumes and period, offsetting the physical derivative. We believe our derivative instruments continue to be effective in achieving the risk management objectives for which they were intended. As of December 31, 2014, we had derivative instruments in place for a portion of our anticipated production through 2017 for a total of 65,215 BBtu of natural gas and 9,340 MBbls of crude oil. The majority of our derivative contracts are entered into at no cost to us as we hedge our anticipated production at the then-prevailing commodity market prices.As of December 31, 2014, our derivative instruments were comprised of commodity swaps, collars, basis protection swaps and physical sales and purchases.•Collars contain a fixed floor price and ceiling price (call). If the index price falls below the fixed put strike price, we receive the market price from the purchaser and receive the difference between the put strike price and index price from the counterparty. If the index price exceeds the fixed call strike price, we receive the market price from the purchaser and pay the difference between the call strike price and index price to the counterparty. If the index price is between the put and call strike price, no payments are due to or from the counterparty;•Swaps are arrangements that guarantee a fixed price. If the index price is below the fixed contract price, we receive the market price from the purchaser and receive the difference between the index price and the fixed contract price from the counterparty. If the index price is above the fixed contract price, we receive the market price from the purchaser and pay the difference between the index price and the fixed contract price to the counterparty. If the index price and contract price are the same, no payment is due to or from the counterparty; •Basis protection swaps are arrangements that guarantee a price differential for natural gas from a specified delivery point. For CIG-basis protection swaps, which had a negative differential to NYMEX for the majority of 2014, we receive a payment from the counterparty if the price differential is greater than the stated terms of the contract and pay the counterparty if the price differential is less than the stated terms of the contract. If the market price and contract price are the same, no payment is due to or from the counterparty; and •Physical sales and purchases are derivatives for fixed-priced physical transactions where we sell or purchase third-party supply at fixed rates. These physical derivatives are offset by financial swaps: for a physical sale the offset is a swap purchase and for a physical purchase the offset is a swap sale.         The following table presents the balance sheet location and fair value amounts of our derivative instruments on the consolidated balance sheets as of December 31, 2014 and 2013: Derivative instruments: Balance sheet line item 2014 2013     (in thousands)Derivative assets:Current       Commodity contracts       Related to crude oil and natural gas sales Fair value of derivatives $186,886 $1,086 Related to natural gas marketing Fair value of derivatives 590 361 Basis protection contracts       Related to crude oil and natural gas sales Fair value of derivatives 19 74     187,495 1,521 Non-current       Commodity contracts       Related to crude oil and natural gas sales Fair value of derivatives 112,599 4,225 Related to natural gas marketing Fair value of derivatives 220 278     112,819 4,503Total derivative assets    $300,314 $6,024        Derivative liabilities:Current       Commodity contracts       Related to crude oil and natural gas sales Fair value of derivatives $— $14,437 Related to natural gas marketing Fair value of derivatives 545 247 Basis protection contracts       Related to crude oil and natural gas sales Fair value of derivatives 25 — Related to natural gas marketing Fair value of derivatives — 5     570 14,689 Non-current       Commodity contracts       Related to crude oil and natural gas sales Fair value of derivatives — 2,609 Related to natural gas marketing Fair value of derivatives 197 233     197 2,842Total derivative liabilities    $767 $17,531    The following table presents the impact of our derivative instruments on our consolidated statements of operations: Year Ended December 31,Consolidated statement of operations line item 2014 2013 2012  Commodity price risk management gain (loss), net      Net settlements $(837) $11,177 $43,591Net change in fair value of unsettled derivatives 311,141 (35,096) (14,312)Total commodity price risk management gain (loss), net $310,304 $(23,919) $29,279Sales from natural gas marketing      Net settlements $(208) $446 $2,170Net change in fair value of unsettled derivatives 364 429 (1,658)Total sales from natural gas marketing $156 $875 $512Cost of natural gas marketing      Net settlements $346 $(257) $(2,029)Net change in fair value of unsettled derivatives (451) (412) 1,601Total cost of natural gas marketing $(105) $(669) $(428)      All of our financial derivative agreements contain master netting provisions that provide for the net settlement of all contracts through a single payment in the event of early termination. Our fixed-price physical purchase and sale agreements that qualify as derivative contracts are not subject to master netting provisions and are not significant. We have elected not to offset the fair value positions recorded on our consolidated balance sheets.The following table reflects the impact of netting agreements on gross derivative assets and liabilities as of December 31, 2014 and 2013:As of December 31, 2014 Derivative instruments, recorded in consolidated balance sheet, gross Effect of master netting agreements Derivative instruments, net  (in thousands)Asset derivatives:      Derivative instruments, at fair value $300,314 $(29) $300,285       Liability derivatives:      Derivative instruments, at fair value $767 $(29) $738       As of December 31, 2013 Derivative instruments, recorded in consolidated balance sheet, gross Effect of master netting agreements Derivative instruments, net  (in thousands)Asset derivatives:      Derivative instruments, at fair value $6,024 $(4,637) $1,387       Liability derivatives:      Derivative instruments, at fair value $17,531 $(4,637) $12,894        |

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| - Definition
The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.
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