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SIGNIFICANT ACCOUNTING POLICIES (Credit Concentration) (Details) - customer | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Accounts receivable |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |
Concentration risk benchmark | 10.00% | 10.00% |
Concentration risk number of major customers over benchmark | 0 | 0 |
Total Revenues |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |
Concentration risk benchmark | 10.00% | 10.00% | 10.00%
Concentration risk number of major customers over benchmark | 0 | 0 | 0

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- Definition Concentration Risk Major Customers Over Benchmark + References No definition available. + Details
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- Definition Concentration Risk Number of Major Customers Over Benchmark + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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