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BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES Schedule of Deferred Revenue (Details) - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2018 | Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |  |  |
Deferred Revenue (Current) | $ 21,000,000 | $ 22,400,000 | $ 23,800,000 | $ 16,200,000
Deferred Revenue (Long-Term) | 38,500,000 | 51,400,000 |  | $ 64,300,000
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Customer Supplemental Payments [Member] |  |  |  |
Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |  |  |
Deferred Revenue (Current) |  | 1.4 |  |
Other Current Liabilities [Member] |  |  |  |
Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |  |  |
Increase (Decrease) | (2,800,000) | 6,200,000 |  |
Other Noncurrent Liabilities [Member] |  |  |  |
Revenue, Initial Application Period Cumulative Effect Transition [Line Items] |  |  |  |
Increase (Decrease) | $ (12,900,000) | $ (12,900,000) |  |

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