STOCK-BASED PLANS (Summary of Restricted Stock Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Weighted Average Grant Date Fair Value
Stock based compensation expense	$ 6,707	$ 7,284	$ 8,200
Stock Options
Weighted Average Grant Date Fair Value
Weighted-average period for recognition of unamortized restricted stock expense	3 years 4 months 24 days
Restricted Stock
Restricted stock activity
Vesting period	5 years
Restricted stock outstanding at the beginning of the period (in shares)	242,556	172,690	122,334
Granted (in shares)	136,198	81,581	61,750
Vested (in shares)	(37,670)	(7,546)	(11,394)
Forfeited (in shares)	(51,972)	(4,169)
Restricted stock outstanding at the end of the period (in shares)	289,112	242,556	172,690
Weighted Average Grant Date Fair Value
Restricted stock outstanding at the beginning of the period (in dollars per share)	$ 100.15	$ 92.02	$ 75.21
Granted (in dollars per share)	67.80	121.81	126.38
Vested (in dollars per share)	83.47	147.56	97.72
Forfeited (in dollars per share)	90.14	101.33
Restricted stock outstanding at the end of the period (in dollars per share)	$ 88.88	$ 100.15	$ 92.02
Stock based compensation expense	$ 4,500	$ 4,700	$ 3,900
Fair value of restricted stock vested	3,900
Unamortized restricted stock expense	$ 13,700
Weighted-average period for recognition of unamortized restricted stock expense	3 years 18 days