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, 2017	Mar. 31, 2016	Dec. 31, 2016
Shares
Outstanding, beginning of year (in shares)	193,114
Exercised (in shares)	(75,297)
Outstanding at end of period (in shares)	117,817		193,114
Exercisable end of period (in shares)	106,413
Weighted Average Exercise Price
Outstanding, beginning of year (in dollars per share)	$ 12.09
Exercised (in dollars per share)	13.25
Outstanding, period end (in dollars per share)	11.34		$ 12.09
Exercisable at end of period (in dollars per share)	$ 10.82
Stock options vested and currently exercisable
Outstanding at end of period, Weighted average remaining contractual term (years)	4 years 8 months 12 days
Outstanding at end of period, Aggregate intrinsic value	$ 2,544
Exercisable at end of period, Weighted average remaining contractual term (years)	4 years 4 months 24 days
Exercisable at end of period, Aggregate intrinsic value	$ 2,353
Stock options
Shares
Granted (in shares)	0	0
Exercisable end of period (in shares)	106,413		181,710
Weighted Average Exercise Price
Exercisable at end of period (in dollars per share)	$ 10.82		$ 11.83
Stock options vested and currently exercisable
Exercisable at end of period, Weighted average remaining contractual term (years)	4 years 4 months 24 days		3 years 9 months 18 days
Exercisable at end of period, Aggregate intrinsic value	$ 2,353		$ 4,101