SHARE-BASED COMPENSATION (Stock/Stock Unit Award Activity) (Details) - Stock and Stock Unit Awards $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) $ / shares shares
Share-based Compensation
Total unrecognized compensation cost related to nonvested share-based compensation \| $	$ 12.7
Total unrecognized compensation cost, recognized over a weighted-average period	1 year 7 months 9 days
Stock/Stock Unit Award Activity and Related Information, Shares
Non-vested at beginning of period, shares \| shares	403
Awarded, shares \| shares	92
Vested, shares \| shares	(107)
Forfeited, shares \| shares	(7)
Non-vested at end of period, shares \| shares	381
Stock/Stock Unit Award Activity and Related Information, Weighted Average Grant Date Fair Value
Non-vested at beginning of period, weighted-average grant date fair value \| $ / shares	$ 49.34
Awarded, weighted-average grant date fair value \| $ / shares	73.15
Vested, weighted-average grant date fair value \| $ / shares	41.45
Forfeited, weighted-average grant date fair value \| $ / shares	43.34
Non-vested at the end of period, weighted-average grant date fair value \| $ / shares	$ 57.41

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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

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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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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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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- Definition

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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- 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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