ACCUMULATED OTHER COMPREHENSIVE INCOME (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2017	Mar. 25, 2016
Accumulated Other Comprehensive Loss, Net of Tax [Roll Forward]
Balance at beginning of period	$ (11,433)	$ (14,013)
Current-period other comprehensive income	2,537	2,477
Balance at end of period	(8,896)	(11,536)
Foreign currency translation adjustment
Accumulated Other Comprehensive Loss, Net of Tax [Roll Forward]
Balance at beginning of period	(11,684)	(13,514)
Foreign currency translation adjustment, net of tax	1,800	2,401
Balance at end of period	(9,884)	(11,113)
Unrealized gain (loss) on marketable securities
Accumulated Other Comprehensive Loss, Net of Tax [Roll Forward]
Balance at beginning of period	251	(499)
Unrealized gain (loss) on investments, net of tax	737	76
Balance at end of period	$ 988	$ (423)