REAL ESTATE PROPERTIES HELD FOR INVESTMENT - Narrative (Details)	12 Months Ended
	Dec. 31, 2015 USD ($) Customer acquisition	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Real Estate Properties [Line Items]
Number of real estate acquisitions | acquisition	3
Estimated earn-out value	$ 10,500,000
Contingent consideration asset	350,000	$ 0
Change in fair value of contingent consideration	$ 1,550,000	1,560,000	$ (200,000)
Operating lease weighted average remaining term	10 years
Security deposit liability	$ 1,300,000	400,000
Reserve for unpaid cash rents	3,500,000	0
Reserve associated with straight-line rental income	$ 5,300,000	$ 600,000
Sales Revenue, Net [Member] | Customer Concentration Risk [Member]
Real Estate Properties [Line Items]
Number of major customers | Customer	2
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Genesis [Member]
Real Estate Properties [Line Items]
Concentration risk percent	34.20%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Holiday [Member]
Real Estate Properties [Line Items]
Concentration risk percent	16.80%
Minimum [Member]
Real Estate Properties [Line Items]
Operating lease expiration period	1 year
Maximum [Member]
Real Estate Properties [Line Items]
Operating lease expiration period	17 years
Accounts Payable and Accrued Liabilities [Member]
Real Estate Properties [Line Items]
Contingent consideration liability	$ 2,700,000
Prepaid Expenses, Deferred Financing Costs and Other Assets, Net [Member]
Real Estate Properties [Line Items]
Contingent consideration asset	$ 300,000