ACCRUED EXPENSES (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Accrued property and real estate taxes	$ 160.4	$ 154.4
Accrued pass-through costs	68.4	59.7
Payroll and related withholdings	62.3	82.2
Accrued rent	58.4	54.0
Amounts payable to tenants	48.7	60.8
Accrued construction costs	19.5	31.9
Accrued pass-through taxes	12.3	25.3
Accrued treasury stock purchases	1.4	0.0
Accrued income tax payable	1.4	15.3
Other accrued expenses	349.7	370.7
Total accrued expenses	$ 782.5	$ 854.3