STOCK-BASED COMPENSATION (Details 2) (USD $)	3 Months Ended		9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013
Total stock-based compensation expense included in the Company's consolidated statements of operations
Stock-based compensation expense	$ 3,141,000	$ 2,445,000	$ 8,588,000	$ 6,590,000
Unrecognized total compensation cost
Unrecognized stock-based compensation expense related to non-vested stock-based awards	22,400,000		22,400,000
Weighted-average period over which unrecognized stock-based compensation cost is expected to be recognized			2 years 1 month 6 days
Cost of sales
Total stock-based compensation expense included in the Company's consolidated statements of operations
Stock-based compensation expense	271,000	233,000	762,000	686,000
Selling, general and administrative expenses
Total stock-based compensation expense included in the Company's consolidated statements of operations
Stock-based compensation expense	2,508,000	1,921,000	6,809,000	5,114,000
Research and development expense
Total stock-based compensation expense included in the Company's consolidated statements of operations
Stock-based compensation expense	$ 362,000	$ 291,000	$ 1,017,000	$ 790,000