STOCK PLANS - Narrative (Details)	12 Months Ended
Dec. 31, 2018 USD ($) plan shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock incentive plans \| plan	3
Stock-based compensation, pre-tax	$ 9,200,000	$ 9,600,000	$ 10,500,000
Stock-based compensation, after-tax	6,900,000	6,100,000	6,800,000
Compensation cost related to non-vested awards not yet recognized	11,800,000
Compensation cost related to nonvested stock options not yet recognized (less than)	$ 100,000
Weighted average remaining period over which cost to be recognized	1 year 6 months 18 days
Restricted Stock And Restricted Stock Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award restriction period	3 years
Restricted Stock And Restricted Stock Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award restriction period	4 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of options vested (less than)	$ 100,000	100,000	100,000
Intrinsic value, stock options exercised	$ 0	200,000	1,600,000
Options exercised (in shares) \| shares	0
Options granted, weighted average grant date fair value	$ 100,000	0	0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of options vested (less than)	7,400,000	9,500,000	4,900,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of options vested (less than)	$ 1,400,000	$ 9,900,000	$ 0

Represents the number of Stock Incentive Plans.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Fair Value

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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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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- 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.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Number of share options (or share units) exercised during the current period.

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