BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Deferred Rent Receivable and Charges (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Deferred Rent Receivable and Charges
Deferred rent receivable	$ 56,406	$ 64,010
Deferred leasing costs	60,116	76,063
Deferred leasing costs, accumulated amortization	25,338	25,914
Deferred offering costs	2,771	2,060
Other deferred costs	$ 1,414	$ 135