REAL ESTATE AND RELATED LEASE INTANGIBLES, NET - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Gross intangible assets	$ 182.9		$ 182.9		$ 189.5
Accumulated amortization	63.1		63.1		60.9
Net intangible assets	119.8		119.8		128.6
Unamortized favorable/unfavorable lease intangibles	5.9		5.9		8.9
Net increase in operating lease income, amortization of below market lease intangibles	0.7	$ 0.4	1.3	$ 0.7
Unbilled rent receivables	0.8		0.8		0.9
Unencumbered real estates	72.1		72.1		$ 128.7
Revenues from acquisitions	1.4	1.9	1.4	1.9
Net earnings (loss)	0.8	1.5	0.8	$ 1.6
Weighted average amortization period for intangible assets acquired				31 years 10 months 24 days
Above Market Leases
Business Acquisition [Line Items]
Net reduction in operating lease income, amortization of above market leases	$ (0.2)	$ (0.2)	$ (0.4)	$ (0.5)