Committed shares reserved under the stock purchase plans for non employee Directors.

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The term (in years) of performance share awards.

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No definition available.

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The term (in years) when the equity-based award expires as specified in the award agreement.

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No definition available.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Section 50
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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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No definition available.

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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

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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

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

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STOCK-BASED COMPENSATION (Details) $ in Millions	12 Months Ended
STOCK-BASED COMPENSATION (Details) $ in Millions	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, restricted stock and performance shares vesting period (in years)	3 years
Average exercise period for outstanding options (in months)	77 months
Average exercise period for exercisable options (in months)	63 months
Aggregate intrinsic value for outstanding options	$ 5.0
Aggregate intrinsic value for exercisable options	5.0
Total intrinsic value of options exercised	1.3	$ 2.9	$ 26.5
Total unrecognized compensation, unvested	$ 9.9
Total unrecognized compensation, unvested, weighted average recognition period (in years)	1 year 3 months 18 days
Performance share award cycle (in years)	3
Liability recorded for performance shares to be settled in cash	$ 3.3
Stock Purchase Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Committed shares reserved under the stock purchase plans for non employee Directors \| shares	181,064
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option and long-term incentive plans, exercisable period (in years)	10 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation, unvested	$ 5.6
Total unrecognized compensation, unvested, weighted average recognition period (in years)	1 year 2 months 12 days