Derivative Financial Instruments (Derivatives And Hedging-Overall-Subsequent Measurement) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized on Derivative	$ 42,181	$ 2,879	$ 5,064	$ (35,501)
NYMEX Commodity Contracts [Member] | Product Sales Revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized on Derivative	37,150	2,150	5,174	(36,183)
NYMEX Commodity Contracts [Member] | Operating Expenses [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized on Derivative	9,701	1,568	4,517	1,521
Butane Swap Agreements [Member] | Product Purchases [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized on Derivative	$ (4,670)	$ (839)	$ (4,627)	$ (839)