CASH, CASH EQUIVALENTS AND RESTRICTED CASH (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017		Mar. 31, 2017	[2]	Dec. 31, 2016	[2]
Cash and Cash Equivalents [Abstract]
Cash	$ 163,440	$ 283,085
Cash equivalents	228,895	264,765
Total cash and cash equivalents	392,335	547,850	[1]
Restricted cash	18,800	18,554
Total cash, cash equivalents and restricted cash	$ 411,135	$ 566,404		$ 290,743		$ 289,518

[1] As of January 1, 2018, the Company adopted Accounting Standards Update 2014-09, "Revenue from Contracts with Customers (Topic 606)" ("ASC 606"), using the full retrospective method. Accordingly, the Company has recast certain amounts in prior periods presented. See Note 1 below for additional discussion.

[2] As of January 1, 2018, the Company adopted ASC 606 using the full retrospective method. Accordingly, the Company has recast certain amounts in the prior period presented. See Note 1 below for additional discussion.Also as of January 1, 2018, the Company adopted Accounting Standards Update No. 2016-18, "Statement of Cash Flows (Subtopic 230): Restricted Cash," and recast the prior period presented. See Note 1 below for additional discussion.