Derivative Financial Instruments (Oil Derivative Contracts Volume And Weighted Average Price) (Details)	1 Months Ended	12 Months Ended
	Jan. 31, 2012 bbl	Dec. 31, 2011 bbl
2012 - Swap Contracts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Volume (Bbl)		3,000
Average Price per Bbl		79.32
2012 - Collar Contracts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Volume (Bbl)		2,000
2012 - Collar Contracts [Member] | Ceiling [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl		127.00
2012 - Collar Contracts [Member] | Floor [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl		90.00
2012 - Collar Contracts With Short Puts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Volume (Bbl)	11,500	41,610	[1]
2012 - Collar Contracts With Short Puts [Member] | Additional Collar Contracts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Volume (Bbl)	8,500
2012 - Collar Contracts With Short Puts [Member] | Ceiling [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	121.10	118.24	[1]
2012 - Collar Contracts With Short Puts [Member] | Ceiling [Member] | Additional Collar Contracts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	120.47
2012 - Collar Contracts With Short Puts [Member] | Floor [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	95.00	82.36	[1]
2012 - Collar Contracts With Short Puts [Member] | Floor [Member] | Additional Collar Contracts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	95.00
2012 - Collar Contracts With Short Puts [Member] | Short Put [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	80.00	66.52	[1]
2012 - Collar Contracts With Short Puts [Member] | Short Put [Member] | Additional Collar Contracts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	80.00
2013 - Swap Contracts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Volume (Bbl)		3,000
Average Price per Bbl		81.02
2013 - Collar Contracts With Short Puts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Volume (Bbl)	32,250	34,000	[1]
2013 - Collar Contracts With Short Puts [Member] | Ceiling [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	121.62	119.38	[1]
2013 - Collar Contracts With Short Puts [Member] | Floor [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	93.45	84.35	[1]
2013 - Collar Contracts With Short Puts [Member] | Short Put [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	76.90	66.56	[1]
2014 - Collar Contracts With Short Puts [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Volume (Bbl)	13,000	10,000	[1]
2014 - Collar Contracts With Short Puts [Member] | Ceiling [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	118.78	127.46	[1]
2014 - Collar Contracts With Short Puts [Member] | Floor [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	90.00	87.50	[1]
2014 - Collar Contracts With Short Puts [Member] | Short Put [Member]
Trading Activity, Gains and Losses, Net [Line Items]
Average Price per Bbl	70.00	72.50	[1]

[1] During the period from January 1, 2012 to February 24, 2012, the Company entered into additional collar contracts with short puts for (i) 8,500 Bbls per day of the Company's July through September 2012 production with a ceiling price of $120.47 per Bbl, a floor price of $95.00 per Bbl and a short put price of $80.00 per Bbl, (ii) 11,500 Bbls per day of the Company's October through December 2012 production with a ceiling price of $121.10 per Bbl, a floor price of $95.00 per Bbl and a short put price of $80.00 per Bbl, (iii) 32,250 Bbls per day of the Company's 2013 production with a ceiling price of $121.62 per Bbl, a floor price of $93.45 per Bbl and a short put price of $76.90 per Bbl and (iv) 13,000 Bbls per day of the Company's 2014 production with a ceiling price of $118.78 per Bbl, a floor price of $90.00 per Bbl and a short put price of $70.00 per Bbl.