SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Supplement Disclosures Related to Consolidated Statements of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accounting Policies [Abstract]
Total interest costs incurred	$ 13,534	$ 14,277
Interest capitalized	185	457
Interest expense	13,349	13,820
Cash paid for interest, net of amounts capitalized	13,301	14,059
Cash paid for income taxes	157	31
Accounts payable and accrued liabilities for construction in progress	12,838	5,674
Accrued leasing commissions	663	710
Reduction to capital for prepaid offering costs	$ 0	$ 176