Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011
Condensed Consolidated Statements of Comprehensive Income [Abstract]
Net income	$ 36,386	$ 26,908	$ 67,490	$ 33,231
Other comprehensive loss, net of tax effects:
Foreign currency translation loss	(2,366)	5,725	(4,832)	5,605
Changes in unrealized holding gains or losses on available-for-sale securities, net of reclassification adjustment for realized gains and losses	(1,017)	(7,709)	(1,021)	(8,078)
Changes in defined benefit plan liabilities	84	45	54	13
Total other comprehensive loss, net of tax effects	(3,299)	(1,939)	(5,799)	(2,460)
Comprehensive income	$ 33,087	$ 24,969	$ 61,691	$ 30,771