Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2012

Fair Value Measurements

Assets and liabilities measured at fair value on a recurring basis

	Fair Value Measurements at June 30, 2012 Using						Netting and			Total Fair
Description	Level 1		Level 2		Level 3		Collateral (a)			Value
Assets:
Commodity derivatives	$	684	$	745	$	—	$	(1,197	)	$	232
Liabilities:
Commodity derivatives	$	627	$	893	$	—	$	(1,272	)	$	248

	Fair Value Measurements at December 31, 2011 Using						Netting and			Total Fair
Description	Level 1		Level 2		Level 3		Collateral (a)			Value
Assets:
Commodity derivatives	$	310	$	640	$	—	$	(758	)	$	192
Liabilities:
Commodity derivatives	$	311	$	652	$	—	$	(782	)	$	181

(a)Represents the impact of netting assets, liabilities and collateral when a legal right of offset exists.