CONDENSED CONSOLIDATED STATEMENT OF UNITHOLDERS' CAPITAL (Unaudited) (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2011
Balance Beginning		$ 2,788,216
Sale of units, net of underwriting discounts and expenses of $26,315		622,656
Sale of units, net of underwriting discounts and expenses of $26,315 (in shares)		16,726,067
Issuance of units		4,452
Distributions to unitholders		(222,391)
Unit-based compensation expenses		11,181
Excess tax benefit from unit-based compensation		4,657
Net income (loss)	237,109	(209,573)
Balance Ending	2,999,198	2,999,198
Units [Member]
Balance Beginning (in shares)		159,010,000
Sale of units, net of underwriting discounts and expenses of $26,315 (in shares)		16,726,000
Issuance of units (in shares)		1,245,000
Balance Ending (in shares)	176,981,000	176,981,000
Unitholders' Capital [Member]
Balance Beginning		2,549,099
Sale of units, net of underwriting discounts and expenses of $26,315		622,656
Issuance of units		4,452
Distributions to unitholders		(222,391)
Unit-based compensation expenses		11,181
Excess tax benefit from unit-based compensation		4,657
Net income (loss)		0
Balance Ending	2,969,654	2,969,654
Accumulated Income [Member]
Balance Beginning		239,117
Sale of units, net of underwriting discounts and expenses of $26,315		0
Issuance of units		0
Distributions to unitholders		0
Unit-based compensation expenses		0
Excess tax benefit from unit-based compensation		0
Net income (loss)		(209,573)
Balance Ending	$ 29,544	$ 29,544