INCOME TAXES (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Contingency [Line Items]
Provision for income taxes	$ 63	$ 67	[1]
Income tax provision due to U.S. federal and state income taxes and foreign income taxes	100	$ 100
Unrecognized tax benefits	20,400
Unrecognized tax benefits that would not impact the effective tax rate	19,500
Unrecognized tax benefits increase	2,200
Earnings of foreign subsidiaries to be reinvested indefinitely	$ 2,400
Federal and State Tax Jurisdictions
Income Tax Contingency [Line Items]
Open tax year	2003
Canada, Ireland, United Kingdom and Germany Tax Jurisdictions
Income Tax Contingency [Line Items]
Open tax year	2010

[1] 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.