SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Real Estate Investments, Net (Details)	12 Months Ended
Dec. 31, 2018
Building and Building Improvements \| Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)	7 years
Building and Building Improvements \| Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)	55 years
Equipment \| Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)	2 years
Equipment \| Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)	15 years

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

No definition available.

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