REAL ESTATE AND RELATED LEASE INTANGIBLES, NET - Unaudited Pro Forma (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income	$ 19,466	$ 20,671	$ 57,845	$ 60,207
Net income	49,598	2,798	42,099	89,458
Net loss attributable to noncontrolling interest in consolidated joint ventures	439	85	436	578
Net (income) loss attributable to noncontrolling interest in operating partnership	(22,429)	430	(17,664)	(43,338)
Net income attributable to Class A common shareholders	27,608	3,313	24,871	46,698
Acquisitions
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income	195	1,127	2,475	3,419
Net income	113	693	1,514	1,470
Net loss attributable to noncontrolling interest in consolidated joint ventures	0	0	0	0
Net (income) loss attributable to noncontrolling interest in operating partnership	(48)	(294)	(642)	(623)
Net income attributable to Class A common shareholders	65	399	873	847
Consolidated Pro Forma
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating lease income	19,661	21,798	60,320	63,626
Net income	49,711	3,491	43,613	90,928
Net loss attributable to noncontrolling interest in consolidated joint ventures	439	85	436	578
Net (income) loss attributable to noncontrolling interest in operating partnership	(22,477)	136	(18,306)	(43,961)
Net income attributable to Class A common shareholders	27,673	3,712	25,744	47,545
2016 Acquisitions
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue recorded from acquisitions included in operating lease income	$ 600		$ 1,000
2015 Acquisitions
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenue recorded from acquisitions included in operating lease income		$ 200		$ 6,400