SIGNIFICANT ACCOUNTING POLICIES (Credit Concentration) (Details) - customer	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounts receivable
Restricted Cash and Cash Equivalents Items [Line Items]
Concentration risk number of major customers over benchmark	0	0	0
Concentration risk benchmark (as a percent)	10.00%	10.00%	10.00%
Total Revenues
Restricted Cash and Cash Equivalents Items [Line Items]
Concentration risk number of major customers over benchmark	0	0	0
Concentration risk benchmark (as a percent)	10.00%	10.00%	10.00%