STOCK AWARD PLANS, Employee Plan Outstanding and Exercisable Options (Details) - Employee Stock Award Plan [Member] - Stock Options [Member] $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) $ / shares shares
First Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	$ 46.74
Range of Exercise Prices, upper limit (in dollars per share)	$ 51.23
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	201,276
Weighted Average Remaining Contractual Life	3 years 10 months 24 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 49.97
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	104,306
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 48.79
Second Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	64.65
Range of Exercise Prices, upper limit (in dollars per share)	$ 74.99
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	415,598
Weighted Average Remaining Contractual Life	4 years 1 month 6 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 69.76
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	237,022
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 70.31
Third Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	93.64
Range of Exercise Prices, upper limit (in dollars per share)	$ 96.85
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	33,987
Weighted Average Remaining Contractual Life	3 years 3 months 18 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 94.31
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	33,987
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 94.31
Fourth Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	101.46
Range of Exercise Prices, upper limit (in dollars per share)	$ 104.37
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	35,154
Weighted Average Remaining Contractual Life	3 years 1 month 6 days
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 102.60
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	35,154
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 102.60
Full Exercise Price Range [Member]
Outstanding and Exercisable Stock options [Abstract]
Range of Exercise Prices, lower limit (in dollars per share)	46.74
Range of Exercise Prices, upper limit (in dollars per share)	$ 104.37
Options Outstanding [Abstract]
Number Outstanding (in shares) | shares	686,015
Weighted Average Remaining Contractual Life	4 years
Weighted Average Exercise Price, Options Outstanding (in dollars per share)	$ 66.85
Aggregate Intrinsic Value, Options Outstanding | $	$ 3,284
Options Exercisable [Abstract]
Number Exercisable (in shares) | shares	410,469
Weighted Average Exercise Price, Options Exercisable (in dollars per share)	$ 69.60
Aggregate Intrinsic Value, Options Exercisable | $	$ 1,822