Price Risk Management Assets And Liabilities (Partnership's Derivative Assets And Liabilities, Amount Of Gain/(Loss) Reclassified From AOCI Into Income (Effective Portion)) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	$ 5,116	$ 5,145	$ 27,069	$ 17,660
Amount of Gain (Loss) Recognized in Income on Ineffective Portion	(112)	241	351	346
Amount of Gain/(Loss) Recognized in Income representing hedge ineffectiveness and amount excluded from the assessment of effectiveness	(3,559)	9,968	18,732	9,001
Amount of Gain (Loss) Recognized In Income On Derivatives	(59,420)	(2,525)	(60,531)	(1,853)
Commodity Derivatives [Member]
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	5,116	6,780	27,069	19,153
Amount of Gain (Loss) Recognized in Income on Ineffective Portion	(112)	241	351	346
Amount of Gain/(Loss) Recognized in Income representing hedge ineffectiveness and amount excluded from the assessment of effectiveness	(3,559)	9,968	18,732	9,001
Amount of Gain (Loss) Recognized In Income On Derivatives	9,175	9,438	4,174	10,110
Interest Rate Derivatives [Member]
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	0	(1,635)	0	(1,493)
Amount of Gain (Loss) Recognized In Income On Derivatives	$ (68,595)	$ (11,963)	$ (64,705)	$ (11,963)