MEMBERS' EQUITY Table 1 (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Changes to our members’ equity
Balance as of December 31, 2010	$ 506,883
Net income	11,046	10,183
Distributions to unitholders	(21,708)	(20,422)
Other comprehensive loss	(5,760)
Unit-based compensation and other	374
Balance as of March 31, 2012	$ 490,835