Equity (Distributions) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2015	Jun. 30, 2015
Incentive Distribution Made to Managing Member or General Partner [Line Items]
General Partners' Cumulative Cash Distributions	$ 16	$ 0
Incentive Distribution, Distribution	16	0
General Partner Distributions	0	0
Distribution Made to Limited Partner, Cash Distributions Paid	15,559	10,982
Partners' Capital Account, Distributions	15,575	10,982
Dividend Arrearges, Common Limited Partner Units	0
Distribution Made to Limited Partner, Distributions Declared, Per Unit	$ 0.3325	$ 0.2407
Minimum Quarterly Distribution [Member]
Incentive Distribution Made to Managing Member or General Partner [Line Items]
Distribution Payment Targets	$0.2875		0.3306
Subsequent Event [Member]
Incentive Distribution Made to Managing Member or General Partner [Line Items]
Distribution Made to Limited Partner, Distributions Declared, Per Unit				$ 0.3475
Distribution Made to Limited Partner, Distributions Paid, Per Unit					$ 0.3475
Common Units [Member]
Incentive Distribution Made to Managing Member or General Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid	7,974	5,491
Subordinated Units [Member]
Incentive Distribution Made to Managing Member or General Partner [Line Items]
Distribution Made to Limited Partner, Cash Distributions Paid	$ 7,585	$ 5,491