SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Supplement Disclosures Related to Consolidated Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Accounting Policies [Abstract]
Total interest costs incurred			$ 27,327	$ 26,808
Interest capitalized			524	330
Interest expense	$ 13,331	$ 13,129	26,803	26,478
Cash paid for interest, net of amounts capitalized			26,918	26,574
Cash paid for income taxes			554	601
Accounts payable and accrued liabilities for construction in progress			18,141	12,245
Accrued leasing commissions			$ 1,913	$ 7,963