ACCOUNTS PAYABLE AND ACCRUED EXPENSES (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Accounts payable	$ 68,040	$ 28,538
Accrued expenses	60,958	67,298
Accrued salary and benefits	37,167	30,670
Accrued professional fees	14,863	9,303
Accounts payable and accrued expenses	$ 181,028	$ 135,809