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EMPLOYEE BENEFIT PLANS (Information Regarding Stock Options) (Details)	12 Months Ended
	Dec. 31, 2019 $ / shares shares
Share-based Payment Arrangement, Option, Exercise Price Range, End of Period [Abstract]
Number of shares (in shares) | shares	275,658
Weighted- average exercise price (in dollars per share)	$ 267.23
Options Exercisable [Abstract]
Number of shares (in shares) | shares	147,620
Weighted-average exercise price (in dollars per share)	$ 210.96
$102.16 - $142.45
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	102.16
Range of exercise price, maximum, (in dollars per share)	$ 142.45
Share-based Payment Arrangement, Option, Exercise Price Range, End of Period [Abstract]
Number of shares (in shares) | shares	3,522
Weighted-average remaining contractual life (in years)	3 years 2 months 8 days
Weighted- average exercise price (in dollars per share)	$ 102.16
Options Exercisable [Abstract]
Number of shares (in shares) | shares	3,522
Weighted-average exercise price (in dollars per share)	$ 102.16
$142.46 - $188.22
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	142.46
Range of exercise price, maximum, (in dollars per share)	$ 188.22
Share-based Payment Arrangement, Option, Exercise Price Range, End of Period [Abstract]
Number of shares (in shares) | shares	36,600
Weighted-average remaining contractual life (in years)	6 years 2 months 8 days
Weighted- average exercise price (in dollars per share)	$ 182.75
Options Exercisable [Abstract]
Number of shares (in shares) | shares	36,600
Weighted-average exercise price (in dollars per share)	$ 182.75
$188.23 - $197.37
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	188.23
Range of exercise price, maximum, (in dollars per share)	$ 197.37
Share-based Payment Arrangement, Option, Exercise Price Range, End of Period [Abstract]
Number of shares (in shares) | shares	32,200
Weighted-average remaining contractual life (in years)	5 years 2 months 1 day
Weighted- average exercise price (in dollars per share)	$ 193.69
Options Exercisable [Abstract]
Number of shares (in shares) | shares	32,200
Weighted-average exercise price (in dollars per share)	$ 193.69
$197.38 - $202.98
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	197.38
Range of exercise price, maximum, (in dollars per share)	$ 202.98
Share-based Payment Arrangement, Option, Exercise Price Range, End of Period [Abstract]
Number of shares (in shares) | shares	33,600
Weighted-average remaining contractual life (in years)	4 years 1 month 28 days
Weighted- average exercise price (in dollars per share)	$ 201.04
Options Exercisable [Abstract]
Number of shares (in shares) | shares	33,600
Weighted-average exercise price (in dollars per share)	$ 201.04
$202.99 - $273.52
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	202.99
Range of exercise price, maximum, (in dollars per share)	$ 273.52
Share-based Payment Arrangement, Option, Exercise Price Range, End of Period [Abstract]
Number of shares (in shares) | shares	52,135
Weighted-average remaining contractual life (in years)	7 years 1 month 28 days
Weighted- average exercise price (in dollars per share)	$ 204.91
Options Exercisable [Abstract]
Number of shares (in shares) | shares	23,066
Weighted-average exercise price (in dollars per share)	$ 204.91
$273.53 - $370.14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	273.53
Range of exercise price, maximum, (in dollars per share)	$ 370.14
Share-based Payment Arrangement, Option, Exercise Price Range, End of Period [Abstract]
Number of shares (in shares) | shares	69,301
Weighted-average remaining contractual life (in years)	8 years 1 month 28 days
Weighted- average exercise price (in dollars per share)	$ 342.13
Options Exercisable [Abstract]
Number of shares (in shares) | shares	18,632
Weighted-average exercise price (in dollars per share)	$ 342.13
$370.15 - $398.15
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price, minimum, (in dollars per share)	370.15
Range of exercise price, maximum, (in dollars per share)	$ 398.15
Share-based Payment Arrangement, Option, Exercise Price Range, End of Period [Abstract]
Number of shares (in shares) | shares	48,300
Weighted-average remaining contractual life (in years)	9 years 1 month 6 days
Weighted- average exercise price (in dollars per share)	$ 398.15
Options Exercisable [Abstract]
Number of shares (in shares) | shares	0
Weighted-average exercise price (in dollars per share)	$ 0

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