Income Taxes (Schedule of Effective Tax Rate Reconciliation) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Tax on pre-tax book income (before reduction for noncontrolling interests)	$ 12,673	$ 0	$ 0
Pre-Transaction earnings taxed to partners	(10,634)	0	0
Tax effect of non-controlled earnings post Transaction	(644)	0	0
Change in partnership tax status	(25,244)	0	0
Change in partnership tax status - state benefit	(1,320)	0	0
State tax expense, net	315	327	231
Perm items - other	1	0	0
Total income tax (benefit) provision	$ (24,853)us-gaap_IncomeTaxExpenseBenefit	$ 327us-gaap_IncomeTaxExpenseBenefit	$ 231us-gaap_IncomeTaxExpenseBenefit
Effective income tax rate reconciliation, percent	(68.60%)	0.70%	1.10%

Effective Income Tax Rate Reconciliation, Change in Tax Status, Amount

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Effective Income Tax Rate Reconciliation, Change in Tax Status, State Benefit, Amount

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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