REAL ESTATE AND RELATED LEASE INTANGIBLES, NET - Unaudited Pro Forma (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income	$ 20,671	$ 12,810	$ 60,207	$ 38,827
Net income	2,798	37,176	89,458	85,820
Net loss attributable to noncontrolling interest in consolidated joint ventures	85	306	578	451
Net (income) loss attributable to predecessor unitholders	0	0	0	12,628
Net (income) loss attributable to noncontrolling interest in operating partnership	430	(22,826)	(43,338)	(59,086)
Net income attributable to Class A common shareholders	3,313	14,656	46,698	39,813
Acquisitions
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income	240	433	1,077	1,299
Net income	138	(183)	625	307
Net loss attributable to noncontrolling interest in consolidated joint ventures	0	0	0	0
Net (income) loss attributable to predecessor unitholders		0		0
Net (income) loss attributable to noncontrolling interest in operating partnership	(64)	86	(292)	(143)
Net income attributable to Class A common shareholders	73	(97)	332	163
Consolidated Pro Forma
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income	20,911	13,243	61,284	40,126
Net income	2,936	36,993	90,083	86,127
Net loss attributable to noncontrolling interest in consolidated joint ventures	85	306	578	451
Net (income) loss attributable to predecessor unitholders		0		12,628
Net (income) loss attributable to noncontrolling interest in operating partnership	366	(22,740)	(43,630)	(59,229)
Net income attributable to Class A common shareholders	$ 3,386	$ 14,559	$ 47,030	$ 39,976