REAL ESTATE AND RELATED LEASE INTANGIBLES, NET - Unaudited Pro Forma (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income	$ 19,294	$ 19,147
Net income	(11,444)	17,963
Net loss attributable to noncontrolling interest in consolidated joint ventures		(191)
Net (income) loss attributable to noncontrolling interest in operating partnership	$ 5,673	(8,597)
Net income attributable to Class A common shareholders		9,175
Acquisitions
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income		871
Net income		454
Net loss attributable to noncontrolling interest in consolidated joint ventures		0
Net (income) loss attributable to noncontrolling interest in operating partnership		(222)
Net income attributable to Class A common shareholders		231
Consolidated Pro Forma
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income		20,018
Net income		18,417
Net loss attributable to noncontrolling interest in consolidated joint ventures		(191)
Net (income) loss attributable to noncontrolling interest in operating partnership		(8,819)
Net income attributable to Class A common shareholders		9,406
2015 Acquisitions
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue recorded from acquisitions included in operating lease income		$ 1,000