REAL ESTATE - Summary of Estimated Useful Lives of Assets (Details)	9 Months Ended
	Sep. 30, 2018
Building and building improvements | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	1 year
Building and building improvements | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	44 years
Furniture, fixtures and equipment | Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	1 year
Furniture, fixtures and equipment | Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives of assets	4 years