MEMBERS' EQUITY Table 2 (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Our cash distributions applicable to the period in which the distributions were earned
Cash distributions per unit	$ 0.545	$ 0.545	$ 0.545	$ 0.545	$ 2.18	$ 2.11	$ 1.98
Total cash distributions	$ 23,249	$ 23,231	$ 23,236	$ 23,222	$ 92,938	$ 89,860	$ 84,252