Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 24,640	$ 26,585	$ 41,345	$ 34,473
Other comprehensive loss:
Change in unrealized loss on valuation of interest rate swap agreements	(10,864)	0	(30,235)	0
Other comprehensive loss	(10,864)	0	(30,235)	0
Comprehensive income	13,776	26,585	11,110	34,473
Net income attributable to non-controlling interests and private perpetual preferred unitholders	(13,551)	(15,465)	(22,828)	(20,215)
Other comprehensive loss attributable to non-controlling interests	5,900	0	16,540	0
Comprehensive income attributable to common stockholders	$ 6,125	$ 11,120	$ 4,822	$ 14,258