STOCK PLANS AND STOCK BASED COMPENSATION - Activity in Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Shares
Outstanding, beginning of year (in shares)	310,665
Exercised (in shares)	(28,075)
Forfeited or expired (in shares)	(2,625)
Outstanding at end of year	279,965		310,665
Exercisable at year end (in shares)	238,715
Fully vested and expected to vest(in shares)	277,754
Weighted Average Exercise Price
Outstanding, beginning of year (in dollars per share)	$ 12.83
Exercised (in dollars per share)	15.20
Forfeited or expired (in dollars per share)	18.04
Outstanding, period end (in dollars per share)	12.54		$ 12.83
Exercisable at year end (in dollars per share)	12.10
Fully vested and expected to vest (in dollars per share)	$ 12.52
Stock options vested and currently exercisable
Number (in shares)	238,715
Weighted average exercise price (in dollars per share)	$ 12.10
Stock options
Shares
Granted (in shares)	0	0
Exercisable at year end (in shares)	238,715		269,415
Weighted Average Exercise Price
Exercisable at year end (in dollars per share)	$ 12.10		$ 12.48
Stock options vested and currently exercisable
Number (in shares)	238,715		269,415
Weighted average exercise price (in dollars per share)	$ 12.10		$ 12.48
Aggregate intrinsic value	$ 2,145		$ 2,801
Weighted average remaining liffe	3 years 8 months 12 days		3 years 7 months 6 days