STOCK-BASED COMPENSATION - SUMMARY OF RESTRICTED STOCK UNITS AND PERFORMANCE-BASED AWARDS (Details) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Shares	305,269	195,305	138,896	148,508
Granted	158,756	126,874	44,144
Vested in Period	(25,909)	(25,696)	0
Unvested, Weighted Average Fair Value	$ 52.61	$ 60.24	$ 59.33	$ 60.23
Granted, Weighted Average Fair Value	49.56	54.64	62.80
Vested in Period, Weighted Average Fair Value	$ 78.04	$ 42.44	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(22,883)	(44,769)	(53,756)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 69.39	$ 52.11	$ 64.67
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Shares	921,495	363,729	327,798	290,054
Granted	656,717	192,106	122,062
Vested in Period	(83,253)	(136,777)	(64,166)
Unvested, Weighted Average Fair Value	$ 43.15	$ 60.00	$ 57.87	$ 58.11
Granted, Weighted Average Fair Value	37.44	54.13	62.40
Vested in Period, Weighted Average Fair Value	$ 69.17	$ 46.52	$ 67.91
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(15,698)	(19,398)	(20,152)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 56.79	$ 59.62	$ 58.15
Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Shares	305,269
Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Shares	132,838
Share-based Payment Arrangement, Tranche Two [Member] \| Net Income Growth Rate [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Shares	19,797
Share-based Payment Arrangement, Tranche Two [Member] \| Earnings Per Share Growth [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]
Unvested, Shares	152,634

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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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 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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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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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