EQUITY - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	$ 3,426,566	$ 3,437,249	$ 1,004,353	$ 1,015,609
Total accumulated other comprehensive income
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	20,813	11,289	$ (1,628)	$ (1,798)
Foreign currency translation loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	(3,287)	(2,913)
Unrealized gains on cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss)	$ 24,100	$ 14,202