Distributions To Unitholders (Details) - $ / shares			3 Months Ended					6 Months Ended
	May 31, 2017	Feb. 28, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Jun. 30, 2017
Common Units [Member]
Distribution paid per unit			$ 0.4441	$ 0.4375	$ 0.4310	$ 0.4246	$ 0.4183
Aggregate distribution of units								393,291
Class B Preferred
Distribution paid per unit			$ 0.28225	$ 0.2258	$ 0.2258	$ 0.4500	$ 0.4500
Aggregate distribution of units	184,697	208,594