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PENSIONS AND OTHER POSTRETIREMENT BENEFITS PENSIONS AND OTHER POSTRETIREMENT BENEFITS (Unobservable Inputs, Level 3) (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] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 193.4 | $ 188.1 | $ 169.8
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 5.5 | 15.5 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 2.5 | 3.0 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 5.7 | 6.8 |
Defined Benefit Plan, Divestitures, Plan Assets | (8.4) | (7.0) |
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
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
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 1.5 | 3.2 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 2.5 | 3.0 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 5.7 | 1.4 |
Defined Benefit Plan, Divestitures, Plan Assets | (7.8) | (5.5) |
Private Equity Funds [Member] | 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 | 5.5 | 6.2 |
Structured Finance [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 62.1 | 65.4 | 61.0
Defined Benefit Plan, Actual Return on Plan Assets Still Held | (3.3) | 4.4 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.0 | 0.0 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.0 |
Defined Benefit Plan, Divestitures, Plan Assets | 0.0 | 0.0 |
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
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 8.1 | 5.2 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.0 | 0.0 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 5.4 |
Defined Benefit Plan, Divestitures, Plan Assets | (0.6) | (1.5) |
Real Estate [Member] | 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 | 10.0 | 8.7 |
Structured Credit [Member] | 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 | 5.8 | 6.1 |
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
Defined Benefit Plan, Actual Return on Plan Assets Still Held | (0.8) | 2.7 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.0 | 0.0 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.0 |
Defined Benefit Plan, Divestitures, Plan Assets | 0.0 | 0.0 |
Hedge Funds [Member] | 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 | 11.2 | 11.5 |
Fair Value, Inputs, Level 3 [Member] | 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 | 32.5 | 32.5 | 57.3
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 1.0 | 2.8 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.4 | 1.9 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.1 | 0.1 |
Defined Benefit Plan, Divestitures, Plan Assets | (1.5) | (29.6) |
Fair Value, Inputs, Level 3 [Member] | Private Equity Funds [Member] | 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 | 5.5 | 6.2 | 6.0
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 0.3 | 1.0 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.4 | 0.4 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.1 | 0.1 |
Defined Benefit Plan, Divestitures, Plan Assets | (1.5) | (1.3) |
Fair Value, Inputs, Level 3 [Member] | Real Estate [Member] | 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 | 10.0 | 8.7 | 13.2
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 1.3 | 0.9 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.0 | 0.5 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.0 |
Defined Benefit Plan, Divestitures, Plan Assets | 0.0 | (5.9) |
Fair Value, Inputs, Level 3 [Member] | Structured Credit [Member] | 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 | 5.8 | 6.1 | 13.5
Defined Benefit Plan, Actual Return on Plan Assets Still Held | (0.3) | 0.4 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.0 | 0.4 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.0 |
Defined Benefit Plan, Divestitures, Plan Assets | 0.0 | (8.2) |
Fair Value, Inputs, Level 3 [Member] | Hedge Funds [Member] | 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 | 11.2 | 11.5 | $ 24.6
Defined Benefit Plan, Actual Return on Plan Assets Still Held | (0.3) | 0.5 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.0 | 0.6 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.0 |
Defined Benefit Plan, Divestitures, Plan Assets | $ 0.0 | $ (14.2) |

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- Definition Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02)(A) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(iv)(02)(A) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 + Details
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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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