PREFERRED STOCK AND STOCKHOLDERS' EQUITY (Details) (USD $)	9 Months Ended		12 Months Ended	0 Months Ended	1 Months Ended	0 Months Ended	9 Months Ended		0 Months Ended	9 Months Ended		1 Months Ended			1 Months Ended			2 Months Ended	3 Months Ended			0 Months Ended			0 Months Ended			0 Months Ended	1 Months Ended				0 Months Ended	1 Months Ended	0 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 06, 2012 Stock Purchase Agreement CPPIB Private placement	Dec. 31, 2012 Stock Purchase Agreement CPPIB Private placement	Dec. 06, 2012 Williston Basin Assets	Sep. 30, 2013 Williston Basin Assets	Jan. 18, 2013 Williston Basin Assets Petro-Hunt Parties	Aug. 02, 2012 GeoResources	Sep. 30, 2012 GeoResources	Sep. 30, 2012 East Texas Assets	Feb. 29, 2012 February 2012 Warrants	Aug. 30, 2012 GeoResources Warrants GeoResources	Aug. 30, 2012 August 2012 Warrants GeoResources	Apr. 30, 2012 Convertible Preferred Stock Private placement	Mar. 31, 2012 Convertible Preferred Stock Private placement	Feb. 29, 2012 Convertible Preferred Stock Private placement	Apr. 17, 2012 Convertible Preferred Stock Private placement	Jun. 30, 2012 Convertible Preferred Stock Private placement	Mar. 31, 2012 Convertible Preferred Stock Private placement	Mar. 05, 2012 Convertible Preferred Stock Private placement	Jan. 17, 2013 Convertible Preferred Stock Williston Basin Assets	Dec. 06, 2012 Convertible Preferred Stock Williston Basin Assets	Jan. 18, 2013 Convertible Preferred Stock Williston Basin Assets	Aug. 13, 2013 Common Stock	Feb. 08, 2012 Common Stock	Jan. 17, 2013 Common Stock	Apr. 17, 2012 Common Stock Private placement	Mar. 31, 2012 Common Stock Private placement	Jan. 18, 2013 Common Stock Private placement	Mar. 28, 2012 Common Stock Private placement	Jan. 17, 2013 Common Stock Williston Basin Assets	Aug. 02, 2012 Common Stock GeoResources	Aug. 31, 2012 Common Stock East Texas Assets	Sep. 03, 2013 5.75% Series A Convertible Perpetual Preferred Stock	Jun. 18, 2013 5.75% Series A Convertible Perpetual Preferred Stock	Jun. 30, 2013 5.75% Series A Convertible Perpetual Preferred Stock	Sep. 30, 2013 5.75% Series A Convertible Perpetual Preferred Stock item
Preferred stock and stockholders' equity
Shares issued				41,900,000													4,444.4511								43,700,000	73,300,000										345,000
Proceeds from the offering of common stock	$ 222,870,000		$ 452,039,000																						$ 215,200,000	$ 275,000,000
Dividend rate (as a percent)	5.75%		5.75%														8.00%																				5.75%
Preferred stock, par value (in dollars per share)	$ 0.0001		$ 0.0001														$ 0.0001
Number of shares of common stock to be issued upon conversion																														10,000		108,800,000						162.4431
Share price (in dollars per share)				$ 7.16																	$ 90,000							$ 10.99								$ 1,000
Gross proceeds from preferred stock offering		311,556,000														400,000,000
Placement agent fees																14,000,000
Other offering expenses																500,000
Par value of common stock (in dollars per share)	$ 0.0001		$ 0.0001	$ 0.0001																											$ 0.0001
Preferred stock converted into common stock (in shares)								108,800,000																				44,400,000
Conversion price per share (in dollars per share)																												$ 9.00	$ 9.00									$ 6.16
Benefit from conversion of stock (in dollars per share)															$ 1.99
Proceeds from the issuance of the Preferred Stock allocated to additional paid-in capital			88,445,000
Beneficial conversion feature, amortized upon conversion																		88,400,000	87,300,000	1,100,000
Initial amortization period of beneficial conversion feature															71 months
Retained earnings	(1,090,870,000)	(266,500,000)	(274,463,000)
Purchase price						1,500,000,000			1,300,000,000
Cash purchase price						788,200,000	32,181,000		531,500,000	579,497,000	296,139,000
Preferred stock issued																						695,200,000
Preferred stock, conversion price (in dollars per share)																						$ 7.45		$ 7.45								$ 7.45
Liquidation preference per share (in dollars per share)																																					$ 1,000
Number of shares of common stock to be issued upon conversion at initial conversion rate																																						56,000,000
Closing sale price of common stock as minimum percentage of the conversion price to automatically convert preferred stock into common stock																																						150.00%
Minimum number of trading days within 30 consecutive trading days during which the closing sales price of common stock per share must exceed the conversion price for the preferred stocks to be redeemable																																						20
Number of consecutive trading day periods within which the closing sale price of common stock price per share must exceed the conversion price for at least 20 trading days for the preferred stocks to be redeemable																																						30 days
Number of trading days immediately following effective date of fundamental change within which holders will receive specified shares of common stock																																						30
Number of consecutive trading day periods ending on the third business day prior to settlement date																																						5 days
Number of shares of common stock to be issued upon conversion on fundamental change																																						292.3977
Threshold period of dividends in arrears and unpaid which will give holders of the Convertible Preferred Stock voting rights																																						18 months
Number of additional directors that can be appointed by holders of the Convertible Preferred Stock until arrearage is paid in full																																						2
Authorized shares of common stock, after amendment of certificate of incorporation	670,000,000		336,666,666																							336,700,000	670,000,000
Payment for capital commitment	17,313,000	18,535,000			6,000,000							600,000														4,000,000
Authorized shares of common stock, before amendment of certificate of incorporation																										33,300,000
Shares issued																							10,880										51,300,000	20,800,000
Purchase price	222,870,000	275,000,000		300,000,000
Net proceeds received				294,000,000																																335,500,000
Payment of cumulative, declared dividends																																			4,100,000
Number of shares issued as non-cash dividend																																			854,817
Cumulative, undeclared dividends																																						1,700,000
Increase in shares of common stock authorized																											333,300,000
Number of shares of common stock that can be purchased from warrants												36,700,000		1
Exercise price (in dollars per share)												$ 4.50		$ 8.40
Proceeds from issuance of warrants		43,590,000										43,600,000
Warrants outstanding													600,000	1,200,000
Cash Portion (in dollars per share)														$ 20
Cash exercise price per $1.00 received														$ 0.82
Gain on expiration of the warrants	$ 1,600,000