REAL ESTATE - Operating Leases, Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Operating Leased Assets [Line Items]
Deferred rent recognized	$ 2,986	$ 3,026
Deferred rent receivables	83,300		$ 80,000
Incentive to lessee	21,100		21,000
Lease Revenue
Operating Leased Assets [Line Items]
Bad debt expense	4,400	1,400
Operating, Maintenance and Management Expense
Operating Leased Assets [Line Items]
Bad debt expense	0	$ (300)
Other liabilities, at fair value
Operating Leased Assets [Line Items]
Security deposit liability	$ 8,400		$ 8,800
Maximum
Operating Leased Assets [Line Items]
Operating leases, term of contract	17 years 1 month 6 days
Weighted Average
Operating Leased Assets [Line Items]
Operating leases, term of contract	4 years 7 months 6 days