STOCK OPTIONS - Schedule of Nonvested Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Number of Shares
Beginning balance (in shares)	250,700	267,200	267,200
Granted (in shares)	109,200	26,500
Vested (in shares)	(36,840)	(12,300)
Forfeited (in shares)	(4,000)	(16,800)
Ending balance (in shares)	319,060	264,600	250,700	267,200
Weighted-Average Exercise Price
Beginning balance (in USD per share)	$ 23.73	$ 23.72	$ 23.72
Granted (in USD per share)	27.00	23.21
Vested (in USD per share)	25.40	23.00
Forfeited (in USD per share)	23.17	23.17
Ending balance (in USD per share)	$ 24.66	$ 23.74	$ 23.73	$ 23.72
Weighted-Average Remaining Contractual Life in Years
Outstanding	7 years 10 months 10 days	7 years 9 months 26 days	7 years 7 months 24 days	8 years 2 months 19 days
Granted	9 years 10 months 24 days	9 years 7 months 2 days
Vested	9 years 1 month 28 days	8 years 9 months 22 days
Forfeited	7 years 4 months 17 days	8 years 4 months 13 days
Aggregate Intrinsic Value
Outstanding	$ 2,347	$ 70	$ 69	$ 76
Granted	548	21
Vested	244	12
Forfeited	$ 53	$ 14