INCOME TAXES Income taxes - Unrecognized tax benefits (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits	$ 62.0us-gaap_UnrecognizedTaxBenefits	$ 74.5us-gaap_UnrecognizedTaxBenefits	$ 49.9us-gaap_UnrecognizedTaxBenefits
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions	12.6	25.8
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	(22.8)	(1.6)
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions	8.0	9.3
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations	$ (10.3)	$ (8.9)

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

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-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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