Equity-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012 years	Jun. 30, 2011	Jun. 30, 2012 years	Jun. 30, 2011
Equity-Based Compensation [Abstract]
Partnership's LTIP units authorized grants, maximum	5,865,584		5,865,584
LTIP compensation expense	$ 1,000,000	$ 800,000	$ 2,294,000	$ 1,747,000
Common units options, aggregate intrinsic value	300,000		300,000
Common units options, weighted average contractual terms in years	3.9		3.9
Proceeds from the exercise of unit options				700,000
Non-vested phantom units, compensation expense	$ 17,800,000		$ 17,800,000
Non-vested phantom units period, in years	3.8