EMPLOYEE STOCK BENEFIT PLANS (Details 2) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) $ / shares shares
EMPLOYEE STOCK BENEFIT PLANS
Unrecognized Compensation Expense	$ 88.6
Stock options
EMPLOYEE STOCK BENEFIT PLANS
Unrecognized Compensation Expense	$ 6.7
Expected Weighted-Average Period to be Recognized (years)	2 years
Performance share awards
EMPLOYEE STOCK BENEFIT PLANS
Shares granted \| shares	0.1
Weighted-average grant date fair value (in dollars per share) \| $ / shares	$ 84.87
Unrecognized Compensation Expense	$ 10.0
Expected Weighted-Average Period to be Recognized (years)	1 year 2 months 13 days
Restricted stock units
EMPLOYEE STOCK BENEFIT PLANS
Shares granted \| shares	0.5
Weighted-average grant date fair value (in dollars per share) \| $ / shares	$ 87.79
Unrecognized Compensation Expense	$ 71.9
Expected Weighted-Average Period to be Recognized (years)	2 years 7 months 9 days

Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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