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FAIR VALUE MEASUREMENTS (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 USD ($) Transfer | Dec. 31, 2015 USD ($) Transfer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Transfers in out between levels | Transfer | 0 | 0
Fair value of total debt | $ 144.3 | $ 188.1
Carrying amount of long-term debt | 141.2 | 183.5
Investments held in Rabbi Trust [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities measured at fair value | 1.7 | 3.6
Investments held in Rabbi Trust [Member] | SERP [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Gross unrealized gains associated with the investment held in the rabbi trust | 0.7 | 0.7
Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Financial assets accounted at fair value | $ 0.0 | $ 0.0

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