SHARE-BASED COMPENSATION - Schedule of Performance Share Units Activity (Details) - Performance share units - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Stock Units
Balance, beginning of year	1,042
Granted	419
Vested	(153)
Forfeited	(26)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Performance Adjustment	(233)
Balance, end of year	1,049	1,042
Nonvested performance share units that have met the requisite service period and will be released as identified in the grant terms	519
Weighted Average Grant Date Fair Value
Balance, beginning of year	$ 31.52
Granted	29.66	$ 35.49	$ 37.93
Vested	22.80
Forfeited	34.05
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Performance Adjustment, Weighted Average Grant Date Fair Value	22.80
Balance, end of year	$ 33.93	$ 31.52

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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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.

+ References

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- Definition

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).

+ References

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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).

+ References

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The number of equity-based payment instruments, excluding stock (or unit) options, that were adjusted for the performance condition 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 adjusted for the performance condition during the reporting period.

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No definition available.

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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 and that have met the requisite service period and will be released as identified in the grant terms.

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No definition available.

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