Net Income/(Loss) Per Limited Partner Unit (Calculation Of Net Loss Per Limited Partner Unit) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended						9 Months Ended				12 Months Ended
	Sep. 30, 2013		Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012		Dec. 31, 2012
Schedule Of Earnings Per Partner Unit [Line Items]
Net income	$ (21,497)				$ (44,660)		$ 33,943		$ 77,814
Net income (loss) attributable to noncontrolling interest	(222)						(222)
Net income (loss) attributable to predecessor operations					(347)				(30,931)
Distributions to unitholders							(106,226)
Amortization of preferred unit discount	(3,908)				(3,751)		(11,605)		(11,140)
Net income (loss) available to other unitholders	(32,117)				(52,258)		2,646		25,243
General partner's interest in net income (loss)	1,244				3,705		2,014		6,150
Limited partners' interest in net income (loss)	(33,361)				(55,963)		632		19,093
Common unitholders' interest in net income (loss)	(33,361)				(46,930)		632		16,717
Subordinated unitholders' interest in net income (loss)					(9,033)				2,376
Weighted average preferred units outstanding	16,666,667				16,666,667		16,666,667		16,666,667
Limited Partners - Public And Affiliated Common Units [Member]
Schedule Of Earnings Per Partner Unit [Line Items]
Unitholders' (basic) (in dollars per unit)	$ (0.57)				$ (1.25)		$ 0.01		$ 0.49
Unitholders' (diluted) (in dollars per unit)	$ (0.57)				$ (1.25)		$ 0.01		$ 0.49
Common units (basic) (in units)	58,572,000	[1]			37,425,000	[1]	58,494,000	[1]	34,347,000	[1]
Common units (diluted) (in units)	58,572,000	[1]			37,425,000	[1]	58,494,000	[1]	34,347,000	[1]
Limited Partners-Affiliated - Subordinated [Member]
Schedule Of Earnings Per Partner Unit [Line Items]
Unitholders' (basic) (in dollars per unit)					$ (1.26)				$ 0.33
Unitholders' (diluted) (in dollars per unit)					$ (1.26)				$ 0.33
Subordinated units (basic and diluted) (in units)					7,146,000	[1]			7,146,000	[1]
Class B Units [Member]
Schedule Of Earnings Per Partner Unit [Line Items]
Distributions to unitholders	(2,990)		(2,990)	(2,990)			(8,970)				(2,990)
Weighted average Class B units outstanding	6,133,558				0		5,987,364		0
Class C Convertible Preferred [Member]
Schedule Of Earnings Per Partner Unit [Line Items]
Distributions to unitholders	$ (3,500)				$ (3,500)		$ (10,500)		$ (10,500)

[1] For the three and nine months ended September 30, 2013 and 2012, we had weighted average preferred units outstanding of 16,666,667. For the three months ended September 30, 2013 and 2012, we had weighted average Class B units outstanding of 6,133,558 and zero. For the nine months ended September 30, 2013 and 2012, we had weighted average of Class B units outstanding of 5,987,364 and zero, respectively. The preferred and Class B units are contingently convertible into common units and could potentially dilute earnings per unit in the future. The preferred and Class B units have not been included in the diluted earnings per unit calculation for the three and nine months ended September 30, 2013, as they were anti-dilutive for the periods. The preferred units were not included in the diluted earnings per unit calculation for the three and nine months ended September 30, 2012, as they were anti-dilutive for the periods.