OVERVIEW AND BASIS OF PRESENTATION (TABLES) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	$ 132,914	$ 82,407	$ 78,237
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	159,015	105,591	$ 78,237	$ 74,437
Prepaid Expenses and Other Current Assets [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 26,101	23,172
Other Noncurrent Assets [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents		$ 12