SEGMENT REPORTING - Geographic data (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2016	Jul. 04, 2015	Jul. 02, 2016	Jul. 04, 2015
GEOGRAPHIC DATA
Net Sales	$ 319,691	$ 281,118	$ 594,113	$ 536,434
% to Total	100.00%	100.00%	100.00%	100.00%
Domestic
GEOGRAPHIC DATA
Net Sales	$ 264,175	$ 229,597	$ 482,365	$ 427,181
% to Total	82.60%	81.70%	81.20%	79.60%
International
GEOGRAPHIC DATA
Net Sales	$ 55,516	$ 51,521	$ 111,748	$ 109,253
% to Total	17.40%	18.30%	18.80%	20.40%