RETIREMENT PLAN (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 01, 2016	Dec. 31, 2014	Dec. 31, 2013
RETIREMENT PLAN
Employer matching contribution (as a percent)	0.25%
Voluntary contribution by participating employee (as a percent)	5.00%
Requisite service period for eligibility of employer matching contribution	1 year
Retirement plan expense	$ 1,080	$ 910	$ 550