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, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Amount of Gain (Loss) Recognized In Income On Derivatives	$ (1,921)	$ (59,420)	$ (28,753)	$ (60,531)
Commodity Derivatives - Trading [Member]
Amount of Gain (Loss) Recognized In Income On Derivatives	4,196	0	(7,099)	0
Commodity Derivatives [Member]
Amount of Gain/(Loss) Reclassified from AOCI into Income (Effective Portion)	3,601	5,116	13,652	27,069
Amount of Gain (Loss) Recognized in Income on Ineffective Portion	(63)	(112)	(17)	351
Amount of Gain/(Loss) Recognized in Income representing hedge ineffectiveness and amount excluded from the assessment of effectiveness	4,230	(3,559)	28,887	18,732
Amount of Gain (Loss) Recognized In Income On Derivatives	(6,052)	9,175	(13,567)	4,174
Interest Rate Derivatives [Member]
Amount of Gain (Loss) Recognized In Income On Derivatives	$ (65)	$ (68,595)	$ (8,087)	$ (64,705)