STOCK-BASED COMPENSATION (Restricted Stock and Restricted Stock Units Activity) (Details) shares in Thousands	3 Months Ended
Mar. 31, 2021 $ / shares shares
Service Period \| Equity Classified Award \| Equity-Settled Award \| Restricted Stock
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	9
Awards granted (in shares) \| shares	0
Awards vested (in shares) \| shares	0
Awards forfeited/cancelled (in shares) \| shares	0
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	9
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 167.18
Awards granted \| $ / shares	0
Awards vested \| $ / shares	0
Awards forfeited/cancelled \| $ / shares	0
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 167.18
Service Period \| Equity Classified Award \| Equity-Settled Award \| Restricted stock units
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	686
Awards granted (in shares) \| shares	161
Awards vested (in shares) \| shares	(248)
Awards forfeited/cancelled (in shares) \| shares	(6)
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	593
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 162.15
Awards granted \| $ / shares	387.51
Awards vested \| $ / shares	129.61
Awards forfeited/cancelled \| $ / shares	179.08
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 236.71
Service Period \| Liability Classified Award \| Cash-Settled Award \| Restricted stock units
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	175
Awards granted (in shares) \| shares	26
Awards vested (in shares) \| shares	(77)
Awards forfeited/cancelled (in shares) \| shares	0
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	124
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 141.16
Awards granted \| $ / shares	387.74
Awards vested \| $ / shares	119.40
Awards forfeited/cancelled \| $ / shares	148.68
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 206.00
Performance Target \| Equity Classified Award \| Equity-Settled Award \| Restricted Stock
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	9
Awards granted (in shares) \| shares	0
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	9
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 165.87
Awards granted \| $ / shares	0
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 165.87
Performance Target \| Equity Classified Award \| Equity-Settled Award \| Restricted stock units
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	21
Awards granted (in shares) \| shares	0
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	21
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 227.16
Awards granted \| $ / shares	0
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 227.16

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

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-Paragraph 2
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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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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.

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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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STOCK-BASED COMPENSATION (Restricted Stock and Restricted Stock Units Activity) (Details) shares in Thousands	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Service Period \| Equity Classified Award \| Equity-Settled Award \| Restricted Stock
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	9
Awards granted (in shares) \| shares	0
Awards vested (in shares) \| shares	0
Awards forfeited/cancelled (in shares) \| shares	0
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	9
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 167.18
Awards granted \| $ / shares	0
Awards vested \| $ / shares	0
Awards forfeited/cancelled \| $ / shares	0
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 167.18
Service Period \| Equity Classified Award \| Equity-Settled Award \| Restricted stock units
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	686
Awards granted (in shares) \| shares	161
Awards vested (in shares) \| shares	(248)
Awards forfeited/cancelled (in shares) \| shares	(6)
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	593
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 162.15
Awards granted \| $ / shares	387.51
Awards vested \| $ / shares	129.61
Awards forfeited/cancelled \| $ / shares	179.08
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 236.71
Service Period \| Liability Classified Award \| Cash-Settled Award \| Restricted stock units
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	175
Awards granted (in shares) \| shares	26
Awards vested (in shares) \| shares	(77)
Awards forfeited/cancelled (in shares) \| shares	0
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	124
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 141.16
Awards granted \| $ / shares	387.74
Awards vested \| $ / shares	119.40
Awards forfeited/cancelled \| $ / shares	148.68
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 206.00
Performance Target \| Equity Classified Award \| Equity-Settled Award \| Restricted Stock
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	9
Awards granted (in shares) \| shares	0
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	9
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 165.87
Awards granted \| $ / shares	0
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 165.87
Performance Target \| Equity Classified Award \| Equity-Settled Award \| Restricted stock units
Number of Shares
Unvested awards outstanding at January 1, 2021 (in shares) \| shares	21
Awards granted (in shares) \| shares	0
Unvested awards outstanding at March 31, 2021 (in shares) \| shares	21
Weighted Average Grant Date Fair Value Per Share
Unvested awards outstanding at January 1, 2021 \| $ / shares	$ 227.16
Awards granted \| $ / shares	0
Unvested awards outstanding at March 31, 2021 \| $ / shares	$ 227.16