Derivatives (Tables)

12 Months Ended

Dec. 31, 2012

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of information concerning the entity's net positions in open commodity derivatives

The following summarizes information concerning our net positions in open commodity derivatives applicable to periods subsequent to December 31, 2012.  The settlement prices of commodity derivatives are based on NYMEX futures prices.

Swaps

	Oil			Gas
	Bbls	Price		MMBtu (a)	Price
Production Period:
1st Quarter 2013	665,000	$	93.70	400,000	$	3.34
2nd Quarter 2013	648,000	$	93.94	390,000	$	3.34
3rd Quarter 2013	300,000	$	104.60	360,000	$	3.34
4th Quarter 2013	300,000	$	104.60	330,000	$	3.34
2014	600,000	$	99.30	—	$	—
	2,513,000			1,480,000

(a) One MMBtu equals one Mcf at a Btu factor of 1,000.

Schedule of effect of derivative instruments on the consolidated balance sheet

Effect of Derivative Instruments on the Consolidated Balance Sheets

	Fair Value of Derivative Instruments as of December 31, 2012
	Asset Derivatives			Liability Derivatives
	Balance Sheet			Balance Sheet
	Location	Fair Value		Location	Fair Value
		(In thousands)			(In thousands)
Derivatives not designated as hedging instruments:
Commodity derivatives	Fair value of derivatives:			Fair value of derivatives:
	Current	$	7,495	Current	$	—
	Non-current	4,236		Non-current	—
Total		$	11,731		$	—

	Fair Value of Derivative Instruments as of December 31, 2011
	Asset Derivatives			Liability Derivatives
	Balance Sheet			Balance Sheet
	Location	Fair Value		Location	Fair Value
		(In thousands)			(In thousands)
Derivatives not designated as hedging instruments:
Commodity derivatives	Fair value of derivatives:			Fair value of derivatives:
	Current	$	—	Current	$	5,633
	Non-current	—		Non-current	494
Total		$	—		$	6,127

Schedule of gross to net presentation reconciliation of derivative assets and liabilities

Gross to Net Presentation Reconciliation of Derivative Assets and Liabilities

	December 31, 2012
	Assets			Liabilities
	(In thousands)
Fair value of derivatives — gross presentation	$	17,851		$	6,120
Effects of netting arrangements	(6,120		)	(6,120		)
Fair value of derivatives — net presentation	$	11,731		$	—

	December 31, 2011
	Assets			Liabilities
	(In thousands)
Fair value of derivatives — gross presentation	$	26		$	6,153
Effects of netting arrangements	(26		)	(26		)
Fair value of derivatives — net presentation	$	—		$	6,127

Schedule of effect of derivative instruments on the consolidated statement of operations and Comprehensive Income (Loss)

Effect of Derivative Instruments Recognized in Earnings on the Consolidated Statements of Operations and Comprehensive Income (Loss)

	Amount of Gain or (Loss) Recognized in Earnings
	Year Ended December 31, 2012
Location of Gain or (Loss) Recognized in Earnings	Realized			Unrealized		Total
	(In thousands)
Derivatives not designated as hedging instruments:
Commodity derivatives:
Other income (expense) - Gain (loss) on derivatives	$	(3,410	)	$	17,858	$	14,448
Total	$	(3,410	)	$	17,858	$	14,448

	Amount of Gain or (Loss) Recognized in Earnings
	Year Ended December 31, 2011
Location of Gain or (Loss) Recognized in Earnings	Realized		Unrealized		Total
	(In thousands)
Derivatives not designated as hedging instruments:
Commodity derivatives:
Other income (expense) - Gain (loss) on derivatives	$	42,521	$	4,506	$	47,027
Total	$	42,521	$	4,506	$	47,027

	Amount of Gain or (Loss) Recognized in Earnings
	Year Ended December 31, 2010
Location of Gain or (Loss) Recognized in Earnings	Realized		Unrealized			Total
	(In thousands)
Derivatives not designated as hedging instruments:
Commodity derivatives:
Other income (expense) - Gain (loss) on derivatives	$	9,875	$	(9,153	)	$	722
Total	$	9,875	$	(9,153	)	$	722