Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 588	$ (4,566)	$ 2,183	$ (10,148)
Other comprehensive income (loss):
Change in foreign currency translation adjustment	174	(35)	385	(1,979)
Net change on unrealized gains on available-for-sale investments	8	(8)	8	(3)
Other comprehensive income (loss)	182	(43)	393	(1,982)
Comprehensive income (loss)	$ 770	$ (4,609)	$ 2,576	$ (12,130)