EMPLOYEE BENEFIT PLANS (Restrictive Stock Award Activity) (Details)	12 Months Ended
Dec. 31, 2018 $ / shares shares
Performance Based RSAs Without Market Condition [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested restricted stock at beginning of period (in shares) \| shares	363,883
Granted (in shares) \| shares	134,209
Vested (in shares) \| shares	(151,995)
Canceled (in shares) \| shares	(41,936)
Unvested restricted stock at end of period (in shares) \| shares	304,161
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested restricted stock at beginning of period (in dollars per share) \| $ / shares	$ 206.59
Granted (in dollars per share) \| $ / shares	358.51
Vested (in dollars per share) \| $ / shares	193.70
Canceled (in dollars per share) \| $ / shares	258.19
Unvested restricted stock at end of period (in dollars per share) \| $ / shares	$ 272.95
Performance-based RSAs - with Market Condition [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested restricted stock at beginning of period (in shares) \| shares	85,200
Granted (in shares) \| shares	26,160
Vested (in shares) \| shares	(27,360)
Canceled (in shares) \| shares	(7,680)
Unvested restricted stock at end of period (in shares) \| shares	76,320
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Unvested restricted stock at beginning of period (in dollars per share) \| $ / shares	$ 205.08
Granted (in dollars per share) \| $ / shares	380.24
Vested (in dollars per share) \| $ / shares	361.20
Canceled (in dollars per share) \| $ / shares	361.20
Unvested restricted stock at end of period (in dollars per share) \| $ / shares	$ 193.44

No definition available.

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- Definition

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

+ References

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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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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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- Definition

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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-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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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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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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-Publisher FASB
-Name Accounting Standards Codification
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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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