FAIR VALUE MEASUREMENTS AND THE FAIR VALUE OPTION (Schedule of Changes in Level 3 Investments) (Details) (Equity Method Investments [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Equity Method Investments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 68.4	$ 51.4	$ 34.7
Unrealized and realized gains	5.3	10.0	5.7
Unrealized and realized losses	(0.3)	(0.4)	(1.4)
Contributions	10.8	11.6	14.0
Distributions	(3.1)	(4.2)	(1.6)
Ending Balance	$ 81.1	$ 68.4	$ 51.4

Fair Value, Measurements with Unobservable Inputs Reconciliation Recurring Basis, Asset, Unrealized and Realized Gains

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- Definition

Fair Value, Measurements with Unobservable Inputs Reconciliation Recurring Basis, Asset, Unrealized and Realized Losses

+ References

No definition available.

+ Details

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

+ Details

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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