Partners' Capital And Distributions (Narrative) (Details) (USD $)	6 Months Ended
	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Dec. 31, 2012
Partners Capital And Distributions [Line Items]
Common units, issued	88,690,985		88,690,985
Common units, outstanding	88,690,985		88,690,985		82,941,000	81,203,000
Conversion Feature, Minimum Distribution Coverage Ratio	1.1
Distribution paid per common unit	$ 0.5500	$ 0.5350	$ 0.5225	$ 0.5100	$ 0.4975
Waiver Units Class 1 [Member]
Partners Capital And Distributions [Line Items]
Waiver units authorized	1,738,000
Waiver Units Class 3 [Member]
Partners Capital And Distributions [Line Items]
Waiver units authorized	1,750,000
Waiver units issued	1,738,000
Waiver Units Class 4 [Member]
Partners Capital And Distributions [Line Items]
Waiver units authorized	1,750,000
Waiver units issued	1,738,000
Waiver units outstanding	1,738,000
Class A [Member]
Partners Capital And Distributions [Line Items]
Common units, outstanding	88,650,988
Class B [Member]
Partners Capital And Distributions [Line Items]
Common units, outstanding	39,997
Waiver Units [Member]
Partners Capital And Distributions [Line Items]
Waiver units authorized	1,738,233
Class Two [Member]
Partners Capital And Distributions [Line Items]
Conversion Feature, Minimum Distribution Coverage Ratio	1.1
Class Three [Member]
Partners Capital And Distributions [Line Items]
Conversion Feature, Minimum Distribution Coverage Ratio	1.1
Class Four [Member]
Partners Capital And Distributions [Line Items]
Conversion Feature, Minimum Distribution Coverage Ratio	1.1
Conversion feature threshold, quarterly distribution, minimum, per unit	0.52
Waiver Units Class2 [Member]
Partners Capital And Distributions [Line Items]
Waiver units authorized	1,750,000
Waiver units issued	1,738,000