OVERVIEW AND BASIS OF PRESENTATION (TABLES) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	$ 520,369	$ 82,407		$ 82,407
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	542,005	105,591	$ 91,439	$ 78,237
Prepaid Expenses and Other Current Assets [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	21,632	23,172
Other Noncurrent Assets [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 4	$ 12