Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 29, 2014	Mar. 30, 2013
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 1,595	$ (5,582)
Other comprehensive income (loss):
Change in foreign currency translation adjustment	104	(1,944)
Net change on unrealized gains on available-for-sale investments	107	5
Other comprehensive income (loss)	211	(1,939)
Comprehensive income (loss)	$ 1,806	$ (7,521)