LONG-TERM LIABILITIES (Details) (USD $)	3 Months Ended	0 Months Ended
	Mar. 31, 2015	Aug. 11, 2014	Aug. 01, 2017	Dec. 31, 2014
LONG-TERM LIABILITIES
Line of Credit	$ 153,748,000			$ 134,749,000
Convertible Debentures	1,636,000			1,636,000
Senior Notes	300,000,000			300,000,000
Discount on Senior Notes	(3,816,000)			(3,947,000)
Contingent Earn-Out	6,660,000			6,530,000
Asset retirement obligations	30,190,000			29,771,000
Total long-term liabilities	488,418,000			468,739,000
Less current portion	381,000			381,000
Long-term portion	488,037,000			468,358,000
Long-term liabilities
Amount of bond redemptions	0
Line of Credit
Long-term liabilities
Term of credit facility		5 years
Maximum borrowing capacity		750,000,000
Initial borrowing base.		225,000,000
Number of additional redetermination rights in each year	1
Weighted average interest rate (as a percent)	2.43%
Interest expense	1,000,000
Interest accrued, approximate	177,000
Line of Credit | Base Rate
Long-term liabilities
Variable rate basis	Base Rate
Line of Credit | Prime rate
Long-term liabilities
Variable rate basis	Prime Rate
Line of Credit | One month LIBOR
Long-term liabilities
Variable rate basis	one month LIBOR
Additional margin (as a percent)	1.00%
Line of Credit | Federal Funds rate
Long-term liabilities
Variable rate basis	Federal Funds
Additional margin (as a percent)	0.50%
Line of Credit | LIBOR
Long-term liabilities
Variable rate basis	LIBOR
Line of Credit | Minimum
Long-term liabilities
Current ratio	1.0
Annualized consolidated EBITDAX to net interest expense ratio	2.5
Line of Credit | Minimum | One month LIBOR
Long-term liabilities
Base Rate Margin (as a percent)	0.75%
Line of Credit | Minimum | LIBOR
Long-term liabilities
Margin (as a percent)	1.75%
Line of Credit | Maximum | One month LIBOR
Long-term liabilities
Base Rate Margin (as a percent)	1.75%
Line of Credit | Maximum | LIBOR
Long-term liabilities
Margin (as a percent)	2.75%
Secured Convertible Debentures
Long-term liabilities
Percentage of principal amount at which debentures may be converted from the date of issuance until maturity into common stock	100.00%
Conversion price (in dollars per share)	$ 50
Secured Convertible Debentures | Maximum
Long-term liabilities
Percentage of principal amount at which debentures may be converted from the date of issuance until maturity into common stock	10.00%
Senior Note
Long-term liabilities
Percentage on initial purchase price		98.617%
Interest rate (as a percent)	9.00%
Additional interest rate (percent)	1.00%
Senior notes, face amount	300,000,000
Senior note, market value	$ 177,000,000
Senior Note | Minimum
Long-term liabilities
Duration of registered exchange offer left open	20 days
Senior Note | Maximum
Long-term liabilities
Duration of exchange offer to be completed after August 11, 2014	360 days
Percentage of redemption price initial borrowing base			35.00%