STOCK-BASED COMPENSATION (Details - RSA & RSU Rollforwards)	9 Months Ended
Sep. 30, 2019 $ / shares shares
Restricted Stock Units (RSUs)
Nonvested RSUs, Restricted Stock and Restricted Stock Units with Performance Conditions, Number of Shares
Nonvested at the beginning of the period (in shares)	201,568
Granted (in shares)	58,689
Vested (in shares)	(72,908)
Forfeited (in shares)	(32,971)
Nonvested at the end of the period (in shares)	154,378
Nonvested RSUs, Restricted Stock and Restricted Stock Units with Performance Conditions, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share) \| $ / shares	$ 225.48
Granted (in dollars per share) \| $ / shares	317.31
Vested (in dollars per share) \| $ / shares	192.00
Forfeited (in dollars per share) \| $ / shares	288.97
Nonvested at the end of the period (in dollars per share) \| $ / shares	$ 262.64
Restricted Stock Units with performance conditions
Nonvested RSUs, Restricted Stock and Restricted Stock Units with Performance Conditions, Number of Shares
Nonvested at the beginning of the period (in shares)	92,481
Granted (in shares)	0
Vested (in shares)	(40,458)
Forfeited (in shares)	(31,049)
Nonvested at the end of the period (in shares)	20,974
Nonvested RSUs, Restricted Stock and Restricted Stock Units with Performance Conditions, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share) \| $ / shares	$ 182.28
Granted (in dollars per share) \| $ / shares	0
Vested (in dollars per share) \| $ / shares	204.78
Forfeited (in dollars per share) \| $ / shares	212.09
Nonvested at the end of the period (in dollars per share) \| $ / shares	$ 214.58
Restricted Stock with performance conditions
Nonvested RSUs, Restricted Stock and Restricted Stock Units with Performance Conditions, Number of Shares
Nonvested at the beginning of the period (in shares)	71,412
Granted (in shares)	0
Vested (in shares)	(17,853)
Forfeited (in shares)	0
Nonvested at the end of the period (in shares)	53,559
Nonvested RSUs, Restricted Stock and Restricted Stock Units with Performance Conditions, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share) \| $ / shares	$ 340.25
Granted (in dollars per share) \| $ / shares	0
Vested (in dollars per share) \| $ / shares	340.25
Forfeited (in dollars per share) \| $ / shares	0
Nonvested at the end of the period (in dollars per share) \| $ / shares	$ 340.25
Restricted Stock with market conditions
STOCK-BASED COMPENSATION
Maximum number of shared to be earned	44,545
Percentage of target number of shares	167.00%
Performance Awards Earned	29,601
Nonvested RSUs, Restricted Stock and Restricted Stock Units with Performance Conditions, Number of Shares
Nonvested at the beginning of the period (in shares)	26,674
Granted (in shares)	0
Vested (in shares)	0
Forfeited (in shares)	0
Nonvested at the end of the period (in shares)	26,674
Nonvested RSUs, Restricted Stock and Restricted Stock Units with Performance Conditions, Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share) \| $ / shares	$ 340.25
Granted (in dollars per share) \| $ / shares	0
Vested (in dollars per share) \| $ / shares	0
Forfeited (in dollars per share) \| $ / shares	0
Nonvested at the end of the period (in dollars per share) \| $ / shares	$ 340.25

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Share-Based Compensation Arrangement By Share-Based Payment Award, Percentage Of Target Number Of Shares

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

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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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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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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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