INCOME TAXES - EFFECTIVE RATE RECONCILIATION (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Tax at statutory rate	35.00%	35.00%	35.00%
Tax at rates other than the statutory rate	(4.80%)	(84.50%)	(42.50%)
Valuation allowance	47.30%	40.80%	(22.00%)
Net change in tax reserves	8.00%	17.10%	6.00%
Adjustment of deferred tax balances following changes in tax rates	(71.80%)	10.90%	0.00%
Other, net	(2.40%)	4.60%	(1.10%)
Provision for (benefit from) taxes on income	11.30%	23.90%	(24.60%)