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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, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | $ 202.4 | $ 193.4 | $ 188.1
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 12.3 | 5.5 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 3.3 | 2.5 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 8.0 | 5.7 |
Defined Benefit Plan, Divestitures, Plan Assets | (14.6) | (8.4) |
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 | 253.0 | 250.6 | 269.3
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 | 36.1 | 33.1 | 31.2
Defined Benefit Plan, Actual Return on Plan Assets Still Held | (2.7) | 1.5 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 3.7 | 2.5 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 8.0 | 5.7 |
Defined Benefit Plan, Divestitures, Plan Assets | (6.0) | (7.8) |
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 | 4.3 | 5.5 |
Structured Finance [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 63.8 | 62.1 | 65.4
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 10.0 | (3.3) |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | (0.3) | 0.0 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.0 |
Defined Benefit Plan, Divestitures, Plan Assets | (8.0) | 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 | 61.9 | 57.5 | 50.0
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 5.1 | 8.1 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | (0.1) | 0.0 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.0 |
Defined Benefit Plan, Divestitures, Plan Assets | (0.6) | (0.6) |
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 | 11.1 | 10.0 |
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 | 6.9 | 5.8 |
Hedge Funds [Member] |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |
Defined Benefit Plan, Fair Value of Plan Assets | 40.6 | 40.7 | 41.5
Defined Benefit Plan, Actual Return on Plan Assets Still Held | (0.1) | (0.8) |
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 | 11.2 |
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 | 33.5 | 32.5 | 32.5
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 1.9 | 1.0 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.1 | 0.4 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.1 |
Defined Benefit Plan, Divestitures, Plan Assets | (1.0) | (1.5) |
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 | 4.3 | 5.5 | 6.2
Defined Benefit Plan, Actual Return on Plan Assets Still Held | (0.3) | 0.3 |
Defined Benefit Plan, Actual Return on Plan Assets Sold During Period | 0.1 | 0.4 |
Defined Benefit Plan, Business Combinations and Acquisitions, Plan Assets | 0.0 | 0.1 |
Defined Benefit Plan, Divestitures, Plan Assets | (1.0) | (1.5) |
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 | 11.1 | 10.0 | 8.7
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 1.1 | 1.3 |
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 |
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 | 6.9 | 5.8 | 6.1
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 1.1 | (0.3) |
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 |
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 | 11.2 | $ 11.5
Defined Benefit Plan, Actual Return on Plan Assets Still Held | 0.0 | (0.3) |
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 |

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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=65897934&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=65897934&loc=d3e2446-114920 + Details
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- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. + 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=64937038&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=65897934&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Plan Assets -URI http://asc.fasb.org/extlink&oid=6749337 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Plan Assets -URI http://asc.fasb.org/extlink&oid=6520858 + Details
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