STOCK-BASED COMPENSATION (Restricted Stock Unit Activity) (Details)	9 Months Ended
Sep. 30, 2020 $ / shares shares
Time-Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding at January 1, 2020 (in shares) \| shares	480,729
RSU's granted (in shares) \| shares	232,802
Vested (in shares) \| shares	(130,654)
Restricted stock units forfeited (in shares) \| shares	(5,692)
Outstanding at September 30, 2020 (in shares) \| shares	577,185
Weighted Average Grant Date Fair Value
Outstanding, Weighted average grant date fair value at January 1, 2020 (in dollars per share) \| $ / shares	$ 95.45
Granted, Weighted average grant date fair value (in dollars per share) \| $ / shares	86.05
Vested, Weighted average grant date fair value (in dollars per share) \| $ / shares	85.62
Forfeited, Weighted average grant date fair value (in dollars per share) \| $ / shares	99.08
Outstanding, Weighted average grant date fair value at September 30, 2020 (in dollars per share) \| $ / shares	$ 92.33
Performance-Based RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding at January 1, 2020 (in shares) \| shares	181,680
RSU's granted (in shares) \| shares	417,313
Vested (in shares) \| shares	0
Restricted stock units forfeited (in shares) \| shares	(6,714)
Outstanding at September 30, 2020 (in shares) \| shares	592,279
Weighted Average Grant Date Fair Value
Outstanding, Weighted average grant date fair value at January 1, 2020 (in dollars per share) \| $ / shares	$ 117.26
Granted, Weighted average grant date fair value (in dollars per share) \| $ / shares	93.08
Vested, Weighted average grant date fair value (in dollars per share) \| $ / shares	0
Forfeited, Weighted average grant date fair value (in dollars per share) \| $ / shares	108.10
Outstanding, Weighted average grant date fair value at September 30, 2020 (in dollars per share) \| $ / shares	$ 100.29

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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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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- 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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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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