Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2013

Fair Value Measurements [Abstract]

Schedule Of Fair Value Of Financial Assets And Liabilities By Level

As of March 31, 2013		Total		Level 1		Level 2		Level 3
Assets from commodity derivative instruments	$	98,500	$	-	$	98,500	$	-
	$	98,500	$	-	$	98,500	$	-
Liabilities from commodity derivative instruments	$	15,157	$	-	$	15,157	$	-
Liabilities from interest rate derivative instruments		11,209		-		11,209		-
	$	26,366	$	-	$	26,366	$	-
As of December 31, 2012		Total		Level 1		Level 2		Level 3
Assets from commodity derivative instruments	$	122,143	$	-	$	122,143	$	-
	$	122,143	$	-	$	122,143	$	-
Liabilities from commodity derivative instruments	$	13,484	$	-	$	13,484	$	-
Liabilities from interest rate derivative instruments		12,236		-		12,236		-
	$	25,720	$	-	$	25,720	$	-