Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2016	Jul. 04, 2015	Jul. 02, 2016	Jul. 04, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 49,335	$ 58,160	$ 99,897	$ 94,419
Other comprehensive income (loss), net of tax effects:
Foreign currency translation adjustments	(2,307)	(4,528)	1,907	(13,418)
Changes in unrealized holding gains or losses on available-for-sale securities, net of reclassification adjustment for realized gains and losses	(304)	(52)	560	13
Changes in defined benefit plan liabilities	(109)	26	(27)	317
Total other comprehensive income (loss), net of tax effects	(2,720)	(4,554)	2,440	(13,088)
Comprehensive income	$ 46,615	$ 53,606	$ 102,337	$ 81,331