LEASES - Lessee Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Lessee operating leases
Contractual ground lease expense	$ 100	$ 100	$ 200	$ 200
Variable lease expense	0	100	100	200
Operating lease right-of-use asset amortization			1,600	400
Operating lease liabilities amortization			1,500	200
Ground Leases
Lessee operating leases
Contractual ground lease expense	3,216	2,139	6,386	4,278
Variable lease expense	44	143	87	282
Ground Leases | Other operating expense
Lessee operating leases
Total lease expense	$ 3,260	$ 2,282	$ 6,473	$ 4,560