STOCK BASED PLANS (Summary of Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Stock Options
Stock options outstanding at the beginning of the period (in shares)			817,998
Granted (in shares)			21,500
Exercised (in shares)			(6,189)
Forfeited (in shares)			(10,600)
Expired (in shares)			(400)
Stock options outstanding at the end of the period (in shares)	822,309		822,309
Weighted Average Exercise Price
Stock options outstanding at the beginning of the period (in dollars per share)			$ 105.06
Granted (in dollars per share)			105.37
Exercised (in dollars per share)			64.93
Forfeited (in dollars per share)			123.17
Expired (in dollars per share)			116.56
Stock options outstanding at the end of the period (in dollars per share)	$ 105.13		$ 105.13
Stock based compensation expense			$ 6,230	$ 5,705
Stock Option
Weighted Average Exercise Price
Stock based compensation expense	$ 800	$ 1,000	1,500	1,600
Share based compensation costs capitalized	$ 200	$ 600	$ 400	$ 900