| INCOME TAXES - Valuation Allowance (Details) - USD ($) $ in Millions | 12 Months Ended | |
|---|---|---|
| Dec. 31, 2017 | Dec. 31, 2016 | |
| INCOME TAXES | ||
| Increase (decrease) in valuation allowance | $ (86.7) | $ 25.9 | 
| Unrecognized tax benefits, if recognized, would result in adjustments to other tax accounts, primarily deferred taxes | 5.8 | $ 5.4 | 
| Income tax benefit | 0.0 | |
| Tax positions subject to interest or penalties | $ 0.0 | |
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- Definition Represents the total amount of unrecognized tax benefits that, if recognized, would affect the amount of other tax accounts including deferred taxes. No definition available. 
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| X | ||||||||||
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- References No definition available. 
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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