Condensed Consolidated Statement of Equity - USD ($) $ in Thousands	Total	Members' Equity [Member]	Accumulated Earnings (Deficit) [Member]
Balance, beginning at Dec. 31, 2013	$ 2,593,366	$ 2,327,938	$ 265,428
Equity [Roll Forward]
Equity distribution	(150,213)	0	(150,213)
Net income (loss)	101,679		101,679
Balance, ending at Sep. 30, 2014	2,544,832	2,327,938	216,894
Balance, beginning at Jun. 30, 2014	2,562,421	2,327,938	234,483
Equity [Roll Forward]
Equity distribution	(48,626)	0	(48,626)
Net income (loss)	31,037		31,037
Balance, ending at Sep. 30, 2014	2,544,832	2,327,938	216,894
Balance, beginning at Dec. 31, 2014	2,521,045	2,327,938	193,107
Equity [Roll Forward]
Equity distribution	(162,933)	0	(162,933)
Net income (loss)	86,689		86,689
Balance, ending at Sep. 30, 2015	2,444,801	2,327,938	116,863
Balance, beginning at Jun. 30, 2015	2,473,599	2,327,938	145,661
Equity [Roll Forward]
Equity distribution	(57,315)		(57,315)
Net income (loss)	28,517		28,517
Balance, ending at Sep. 30, 2015	$ 2,444,801	$ 2,327,938	$ 116,863