Incentive Compensation - Summary of Incentive Compensation Expense (Details) - 2015 LTIP - General and administrative expenses - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash—long-term incentive plan	$ 4,029	$ 2,506	$ 7,480	$ 5,725
Total incentive compensation expense	9,628	4,772	14,842	12,317
Restricted common and subordinated units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based compensation	2,668	1,716	3,950	3,432
Restricted Performance Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Equity-based compensation	1,260		1,260
Board of Director | Common Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total incentive compensation expense	$ 1,671	$ 550	$ 2,152	$ 3,160