STOCK PLANS AND SHARE BASED COMPENSATION (Performance-based Awards and Restricted Stock Units) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Performance Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance-based awards shares released as a percentage of target number, minimum	0.00%
Number of performance-based awards shares released as a percentage of target number, maximum	200.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments [Roll Forward]
Outstanding, shares	26	79	99	11
Granted, shares	89	88	101
Vested, shares	(79)	(99)	(11)
Forfeited or expired, shares	(63)	(9)	(2)
Outstanding, weighted-average grant date fair value per share, beginning of period	$ 63.99	$ 46.25	$ 52.35
Granted, weighted-average grant date fair value per share	62.87	63.99	46.26
Vested, weighted-average grant date fair value per share	63.99	46.25	52.35
Forfeited or expired, weighted-average grant date fair value per share	62.87	63.99	46.87
Outstanding, weighted-average grant date fair value per share, end of period	$ 62.87	$ 63.99	$ 46.25
Outstanding, weighted-average remaining contractual term (in years)	0 years
Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Outstanding, Aggregate Intrinsic Value	$ 1,610
Outstanding and expected to vest, shares	26
Outstanding and expected to vest, weighted-average remaining contractual term (in years)	0 years
Outstanding and expected to vest, aggregate intrinsic value	$ 1,610
Grant date fair value of awards released	$ 5,100	$ 4,600	$ 600
Long-Term Performance-based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of performance-based awards shares released as a percentage of target number, minimum	0.00%
Number of performance-based awards shares released as a percentage of target number, maximum	200.00%
Performance based period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments [Roll Forward]
Outstanding, shares	213	184	150	129
Granted, shares	72	71	78
Vested, shares	(38)	0	0
Forfeited or expired, shares	(5)	(37)	(57)
Outstanding, weighted-average grant date fair value per share, beginning of period	$ 52.80	$ 47.65	$ 53.75
Granted, weighted-average grant date fair value per share	59.90	63.00	43.26
Vested, weighted-average grant date fair value per share	52.45	0.00	0.00
Forfeited or expired, weighted-average grant date fair value per share	43.26	51.59	55.35
Outstanding, weighted-average grant date fair value per share, end of period	$ 55.48	$ 52.80	$ 47.65
Outstanding, weighted-average remaining contractual term (in years)	1 year 6 months
Outstanding, aggregate intrinsic value	$ 12,963
Outstanding and expected to vest, shares	141
Outstanding and expected to vest, weighted-average remaining contractual term (in years)	9 months 10 days
Outstanding and expected to vest, aggregate intrinsic value	$ 8,611
Grant date fair value of awards released	$ 2,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments [Roll Forward]
Outstanding, shares	895	948	718	681
Granted, shares	275	558	331
Vested, shares	(296)	(284)	(270)
Forfeited or expired, shares	(32)	(44)	(24)
Outstanding, weighted-average grant date fair value per share, beginning of period	$ 55.51	$ 47.54	$ 46.98
Granted, weighted-average grant date fair value per share	62.85	60.82	46.70
Vested, weighted-average grant date fair value per share	53.78	46.52	45.13
Forfeited or expired, weighted-average grant date fair value per share	59.43	50.89	47.21
Outstanding, weighted-average grant date fair value per share, end of period	$ 58.19	$ 55.51	$ 47.54
Outstanding, weighted-average remaining contractual term (in years)	1 year 9 months
Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Outstanding, Aggregate Intrinsic Value	$ 54,575
Outstanding and expected to vest, shares	828
Outstanding and expected to vest, weighted-average remaining contractual term (in years)	1 year 7 months 18 days
Outstanding and expected to vest, aggregate intrinsic value	$ 50,477
Grant date fair value of awards released	$ 15,900	$ 13,200	$ 12,200
Exercise Price Range One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Exercise Price Range, Lower Range Limit	$ 17.75
Options Outstanding, Exercise Price Range, Upper Range Limit	36.95
Exercise Price Range Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Exercise Price Range, Lower Range Limit	37.96
Options Outstanding, Exercise Price Range, Upper Range Limit	$ 42.88

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding and Expected to Vest, Weighted Average Remaining Contractual Term

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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).

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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).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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.

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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.

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Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

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