CONDENSED CONSOLIDATED STATEMENT OF UNITHOLDERS' CAPITAL (Unaudited) (USD $) In Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2011
Balance Beginning		$ 2,788,216
Sale of units, net of underwriting discounts and expenses of $26,685		622,900
Issuance of units		7,156
Cancellation of units		0
Purchase of units		(13,191)
Distributions to unitholders		(344,612)
Unit-based compensation expenses		16,759
Excess tax benefit from unit-based compensation		5,396
Net income	837,627	628,054
Balance Ending	3,710,678	3,710,678
Units [Member]
Balance Beginning (in shares)		159,010
Sale of units, net of underwriting discounts and expenses of $26,685 (in shares)		16,742
Issuance of units (in shares)		1,356
Cancellation of units (in shares)		(400)
Balance Ending (in shares)	176,708	176,708
Unitholders' Capital [Member]
Balance Beginning		2,549,099
Sale of units, net of underwriting discounts and expenses of $26,685		622,900
Issuance of units		7,156
Cancellation of units		(13,191)
Purchase of units		0
Distributions to unitholders		(344,612)
Unit-based compensation expenses		16,759
Excess tax benefit from unit-based compensation		5,396
Net income		0
Balance Ending	2,843,507	2,843,507
Accumulated Income [Member]
Balance Beginning		239,117
Sale of units, net of underwriting discounts and expenses of $26,685		0
Issuance of units		0
Cancellation of units		0
Purchase of units		0
Distributions to unitholders		0
Unit-based compensation expenses		0
Excess tax benefit from unit-based compensation		0
Net income		628,054
Balance Ending	867,171	867,171
Treasury Units (at Cost) [Member]
Balance Beginning		0
Sale of units, net of underwriting discounts and expenses of $26,685		0
Issuance of units		0
Cancellation of units		13,191
Purchase of units		(13,191)
Distributions to unitholders		0
Unit-based compensation expenses		0
Excess tax benefit from unit-based compensation		0
Net income		0
Balance Ending	$ 0	$ 0