COMMON STOCK PLANS - Stock Options, Range of Exercise Prices (Details) - Stock options - Stock Incentive Plan	12 Months Ended
Dec. 31, 2017 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of outstanding options, Range of Exercise Prices, Lower Range Limit (in dollars per share)	$ 29.79
Number of outstanding options, Range of Exercise Prices, Upper Range Limit (in dollars per share)	$ 80.48
Stock Incentive Plan (in shares) \| shares	677,565
Weighted Average Remaining Contractual Life	3 years 10 months 18 days
$60.56
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 60.56
Stock Incentive Plan (in shares) \| shares	48,560
Weighted Average Remaining Contractual Life	24 days
$29.79
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 29.79
Stock Incentive Plan (in shares) \| shares	21,791
Weighted Average Remaining Contractual Life	1 year
$46.69
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 46.69
Stock Incentive Plan (in shares) \| shares	26,481
Weighted Average Remaining Contractual Life	2 years
$54.99
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 54.99
Stock Incentive Plan (in shares) \| shares	101,285
Weighted Average Remaining Contractual Life	3 years
$54.11
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 54.11
Stock Incentive Plan (in shares) \| shares	254,426
Weighted Average Remaining Contractual Life	4 years
$48.36
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 48.36
Stock Incentive Plan (in shares) \| shares	117,446
Weighted Average Remaining Contractual Life	5 years
$80.48
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 80.48
Stock Incentive Plan (in shares) \| shares	3,686
Weighted Average Remaining Contractual Life	5 years 9 months 15 days
$72.39
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 72.39
Stock Incentive Plan (in shares) \| shares	101,451
Weighted Average Remaining Contractual Life	6 years
$79.63
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices (in dollars per share)	$ 79.63
Stock Incentive Plan (in shares) \| shares	2,439
Weighted Average Remaining Contractual Life	6 years

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range

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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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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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