CONSOLIDATED STATEMENTS OF MEMBERS’ EQUITY (USD $) In Thousands, except Share data	Total USD ($)	Units [Member]	Members' Equity [Member] USD ($)	Accumulated Other Comprehensive Income (Loss) [Member] USD ($)
Balance, units, at Dec. 31, 2009		42,514,494
Balance at Dec. 31, 2009	$ 538,208		$ 545,200	$ (6,992)
Net income	72,463		72,463	0
Other comprehensive income (loss)	7,463		0	7,463
Distributions to unitholders	(77,589)		(77,589)	0
Unit-based compensation	918		918	0
Unit-based compensation, units		30,165
Balance, units, at Dec. 31, 2010		42,544,659
Balance at Dec. 31, 2010	541,463		540,992	471
Net income	69,636		69,636	0
Other comprehensive income (loss)	(23,136)		0	(23,136)
Distributions to unitholders	(82,966)		(82,966)	0
Unit-based compensation	1,886		1,886	0
Unit-based compensation, units		13,841
Balance, units, at Dec. 31, 2011		42,558,500
Balance at Dec. 31, 2011	506,883		529,548	(22,665)
Net income	2,128		2,128	0
Other comprehensive income (loss)	(9,357)		0	(9,357)
Distributions to unitholders	(88,345)		(88,345)	0
Unit-based compensation	1,513		1,513	0
Unit-based compensation, units		41,691
Balance, units, at Dec. 31, 2012		42,600,191
Balance at Dec. 31, 2012	$ 412,822		$ 444,844	$ (32,022)