STOCK PLANS AND SHARE BASED COMPENSATION (Performance-based Awards and Restricted Stock Units) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
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	99,000	11,000	0	100,000
Granted, shares	101,000	89,000	83,000
Vested, shares	(11,000)	0	(83,000)
Forfeited or expired, shares	(2,000)	(78,000)	(100,000)
Outstanding, weighted-average grant date fair value per share, beginning of period	$ 52.35	$ 0.00	$ 38.48
Granted, weighted-average grant date fair value per share	46.26	52.36	53.93
Vested, weighted-average grant date fair value per share	52.35	0.00	38.48
Forfeited or expired, weighted-average grant date fair value per share	46.87	52.35	51.30
Outstanding, weighted-average grant date fair value per share, end of period	$ 46.25	$ 52.35	$ 0.00
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	$ 6,714
Outstanding and expected to vest, shares	99,000
Outstanding and expected to vest, weighted-average remaining contractual term (in years)	0 years
Outstanding and expected to vest, aggregate intrinsic value	$ 6,714
Grant date fair value of awards released	$ 600		$ 3,200
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	150,000	129,000	61,000	0
Granted, shares	78,000	72,000	61,000
Vested, shares	0	0	0
Forfeited or expired, shares	(57,000)	(4,000)	0
Outstanding, weighted-average grant date fair value per share, beginning of period	$ 53.75	$ 55.51	$ 0.00
Granted, weighted-average grant date fair value per share	43.26	52.47	55.51
Vested, weighted-average grant date fair value per share	0.00	0.00	0.00
Forfeited or expired, weighted-average grant date fair value per share	55.35	57.76	0.00
Outstanding, weighted-average grant date fair value per share, end of period	$ 47.65	$ 53.75	$ 55.51
Outstanding, weighted-average remaining contractual term (in years)	1 year 6 months 9 days
Outstanding, aggregate intrinsic value	$ 10,177
Outstanding and expected to vest, shares	113,000
Outstanding and expected to vest, weighted-average remaining contractual term (in years)	1 year 6 months 5 days
Outstanding and expected to vest, aggregate intrinsic value	$ 7,659
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	718,000	681,000	692,000	714,000
Granted, shares	331,000	319,000	281,000
Vested, shares	(270,000)	(267,000)	(267,000)
Forfeited or expired, shares	(24,000)	(63,000)	(36,000)
Outstanding, weighted-average grant date fair value per share, beginning of period	$ 46.98	$ 43.86	$ 38.97
Granted, weighted-average grant date fair value per share	46.70	49.75	51.12
Vested, weighted-average grant date fair value per share	45.13	42.49	38.57
Forfeited or expired, weighted-average grant date fair value per share	47.21	45.71	42.74
Outstanding, weighted-average grant date fair value per share, end of period	$ 47.54	$ 46.98	$ 43.86
Outstanding, weighted-average remaining contractual term (in years)	1 year 3 months
Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Outstanding, Aggregate Intrinsic Value	$ 48,684
Outstanding and expected to vest, shares	674,000
Outstanding and expected to vest, weighted-average remaining contractual term (in years)	1 year 2 months 10 days
Outstanding and expected to vest, aggregate intrinsic value	$ 45,711
Grant date fair value of awards released	$ 12,200	$ 11,300	$ 10,300
2007 Equity Incentive Plan [Member] \| Performance Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in number of shares available for issuance under the 2007 Plan per award granted	2.0
2007 Equity Incentive Plan [Member] \| Long-Term Performance-based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in number of shares available for issuance under the 2007 Plan per award granted	2.0
2007 Equity Incentive Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in number of shares available for issuance under the 2007 Plan per award granted	2.0
2016 Incentive Award Plan [Member] \| Performance Based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in number of shares available for issuance under the 2007 Plan per award granted	1
2016 Incentive Award Plan [Member] \| Long-Term Performance-based Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in number of shares available for issuance under the 2007 Plan per award granted	1
2016 Incentive Award Plan [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in number of shares available for issuance under the 2007 Plan per award granted	1

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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- Definition

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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- Definition

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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- Definition

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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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.

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

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