STOCK-BASED COMPENSATION - SCHEDULE OF SHARE-BASED COMPENSATION, STOCK OPTIONS AND STOCK APPRECIATION RIGHTS AWARD ACTIVITY (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangements By Share Based Payment Award, Options and Stock Appreciation Rights Outstanding [Roll Forward]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 47.11	$ 35.01	$ 40.74
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	305,269	195,305	138,896	148,508
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 49.56	$ 54.64	$ 62.80
Share Based Compensation Arrangements By Share Based Payment Award, Options and Stock Appreciation Rights Outstanding [Roll Forward]
Stock-settled appreciation rights granted	158,756	126,874	44,144
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 13.86	$ 16.36	$ 18.38
Share Based Compensation Arrangements By Share Based Payment Award, Options and Stock Appreciation Rights Outstanding [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised	391,339	113,099	192,700
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Forfeitures	46,245	115,103	203,320
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	$ 65.93	$ 65.27	$ 68.69
Weighted Average Remaining Contractual Term, Outstanding	5 years 8 months 12 days
Weighted Average Remaining Contractual Term, Exercisable	4 years 9 months 18 days
Aggregate Intrinsic Value, Outstanding	$ 39,834
Aggregate Intrinsic Value, Exercisable	$ 26,622
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number	1,630,891	1,723,370	1,453,932
Stock-settled appreciation rights granted	262,091	213,618	509,046
Share-based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Exercise Price	$ 62.72	$ 59.00	$ 57.93
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 60.48	$ 59.72	$ 59.26	$ 57.75
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	2,161,556	2,337,049	2,351,633	2,238,607
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 48.32	$ 54.63	$ 62.68
Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	132,838
Share-based Payment Arrangement, Tranche Two [Member] \| Net Income Growth Rate [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	19,797

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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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Number of non-option equity instruments exercised by participants.

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Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Weighted average price of options that were either forfeited or expired.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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- Definition

Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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No definition available.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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Share Based Compensation Arrangements By Share Based Payment Award, Options and Stock Appreciation Rights Outstanding Roll Forward [Roll Forward]

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