PENSION AND POST-RETIREMENT PLANS (Details 3) (Qualified Pension Benefits, USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Changes in plan assets
Balance at the beginning of the period			$ 149.2
Actual return (loss) on plan assets:
Balance at the end of the period	178.9	172.8	149.2
Significant Unobservable Inputs (Level 3)
Actual return (loss) on plan assets:
Balance at the end of the period	9.6	8.9
Significant Unobservable Inputs (Level 3) \| Real estate partnerships interests
Actual return (loss) on plan assets:
Balance at the end of the period	9.3	8.6
Significant Unobservable Inputs (Level 3) \| Private equity partnership interests
Actual return (loss) on plan assets:
Balance at the end of the period	0.3	0.3
Fair Value Measurements Recurring \| Significant Unobservable Inputs (Level 3)
Changes in plan assets
Balance at the beginning of the period	8.9	8.6
Actual return (loss) on plan assets:
Assets held at the reporting date	0.8	0.7
Assets sold during the period	0.3	0.4
Purchases, sales and settlements, net	(0.4)	(0.8)
Balance at the end of the period	9.6	8.9
Fair Value Measurements Recurring \| Significant Unobservable Inputs (Level 3) \| Real estate partnerships interests
Changes in plan assets
Balance at the beginning of the period	8.6	7.8
Actual return (loss) on plan assets:
Assets held at the reporting date	0.8	0.9
Assets sold during the period	0.3	0.3
Purchases, sales and settlements, net	(0.4)	(0.4)
Balance at the end of the period	9.3	8.6
Fair Value Measurements Recurring \| Significant Unobservable Inputs (Level 3) \| Private equity partnership interests
Changes in plan assets
Balance at the beginning of the period		0.8
Actual return (loss) on plan assets:
Assets held at the reporting date		(0.2)
Assets sold during the period		0.1
Purchases, sales and settlements, net		(0.4)
Balance at the end of the period	$ 0.3	$ 0.3

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Actual return on plan assets, separately identifying the amount related to assets sold during the period.

+ 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=28361610&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=28361610&loc=d3e2446-114920

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- Definition

Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

+ References

+ 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 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: 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=29635418&loc=d3e12355-114930

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- Definition

Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations.

+ 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)(B)

-URI http://asc.fasb.org/extlink&oid=28361610&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)(B)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920

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