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PENSIONS AND OTHER POSTRETIREMENT BENEFITS PENSIONS AND OTHER POSTRETIREMENT BENEFITS ( Fair Value of Recurring) (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Current Fiscal Year End Date | --12-31 |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 193.4 | $ 188.1 | $ 169.8
Hedge Funds [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 40.7 | 41.5 | 38.8
Private Equity Funds [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 33.1 | 31.2 | 29.1
Real Estate [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 57.5 | 50.0 | 40.9
Other Postretirement Benefit Plan, Defined Benefit [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 250.6 | 269.3 | 251.8
Other Postretirement Benefit Plan, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 37.9 | 39.1 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 32.5 | 32.5 | 57.3
Other Postretirement Benefit Plan, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 180.2 | 197.7 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Fixed Income Investments [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 196.0 | 213.6 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Fixed Income Investments [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 37.9 | 39.1 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Fixed Income Investments [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Fixed Income Investments [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 158.1 | 174.5 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Hedge Funds [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 11.2 | 11.5 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 11.2 | 11.5 | 24.6
Other Postretirement Benefit Plan, Defined Benefit [Member] | Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Private Equity Funds [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 5.5 | 6.2 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Private Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Private Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 5.5 | 6.2 | 6.0
Other Postretirement Benefit Plan, Defined Benefit [Member] | Private Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Structured Credit [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 5.8 | 6.1 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Structured Credit [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Structured Credit [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 5.8 | 6.1 | 13.5
Other Postretirement Benefit Plan, Defined Benefit [Member] | Structured Credit [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Real Estate [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 10.0 | 8.7 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Real Estate [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Real Estate [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 10.0 | 8.7 | $ 13.2
Other Postretirement Benefit Plan, Defined Benefit [Member] | Real Estate [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Cash [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.1 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Cash [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Cash [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | Cash [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.1 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | U S Small Mid Cap [Member] | Equity Securities [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 2.8 | 2.9 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | U S Small Mid Cap [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | U S Small Mid Cap [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | U S Small Mid Cap [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 2.8 | 2.9 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | International [Member] | Equity Securities [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 8.2 | 8.6 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | International [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | International [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | International [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 8.2 | 8.6 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | U S Large Cap [Member] | Equity Securities [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 11.1 | 11.6 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | U S Large Cap [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | U S Large Cap [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 0.0 | 0.0 |
Other Postretirement Benefit Plan, Defined Benefit [Member] | U S Large Cap [Member] | Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 11.1 | $ 11.6 |

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